OSN 550 V100R007C10 Product Description

OptiX OSN 550 Multi-Service CPE OpticalTransmission System

V100R007C10

Product Description

Issue 02

Date 2014-04-15

HUAWEI TECHNOLOGIES CO., LTD.

Copyright © Huawei Technologies Co., Ltd. 2014. All rights reserved.

No part of this document may be reproduced or transmitted in any form or by any means without prior writtenconsent of Huawei Technologies Co., Ltd. Trademarks and Permissions

and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd.All other trademarks and trade names mentioned in this document are the property of their respective holders. NoticeThe purchased products, services and features are stipulated by the contract made between Huawei and thecustomer. All or part of the products, services and features described in this document may not be within thepurchase scope or the usage scope. Unless otherwise specified in the contract, all statements, information,and recommendations in this document are provided "AS IS" without warranties, guarantees or representationsof any kind, either express or implied.

The information in this document is subject to change without notice. Every effort has been made in thepreparation of this document to ensure accuracy of the contents, but all statements, information, andrecommendations in this document do not constitute a warranty of any kind, express or implied.

Huawei Technologies Co., Ltd.Address: Huawei Industrial Base

Bantian, LonggangShenzhen 518129People's Republic of China

Website: http://www.huawei.com

Email: [email protected]

Issue 02 (2014-04-15) Huawei Proprietary and ConfidentialCopyright © Huawei Technologies Co., Ltd.

i

http://www.huawei.com

mailto:[email protected]

About This Document

Product VersionThe following table lists the product versions applicable to this documentation.

Product Name Product Version

OptiX OSN 550 V100R007C10

iManager U2000 V200R001C00

Intended AudienceThis document describes the OptiX OSN 550 in terms of network application, functions,hardware structure, software architecture, features, and technical specifications.

This document is intended for:

l Network planning engineers

l Data configuration engineers

l System maintenance engineers

Symbol ConventionsThe symbols that may be found in this document are defined as follows.

Symbol Description

DANGER indicates a hazard with a high level or mediumlevel of risk which, if not avoided, could result in death orserious injury.

WARNING indicates a hazard with a low level of riskwhich, if not avoided, could result in minor or moderateinjury.

OptiX OSN 550 Multi-Service CPE Optical TransmissionSystemProduct Description About This Document


ii

Symbol Description

CAUTION indicates a potentially hazardous situation that,if not avoided, could result in equipment damage, data loss,performance deterioration, or unanticipated results.

Provides a tip that may help you solve a problem or save time.

Provides additional information to emphasize or supplementimportant points in the main text.

GUI ConventionsConvention Meaning

Boldface Buttons, menus, parameters, tabs, window, and dialog titles arein boldface. For example, click OK.

> Multi-level menus are in boldface and separated by the ">" signs.For example, choose File > Create > Folder.

Change HistoryChanges between document issues are cumulative. The latest document issue contains all thechanges made in earlier issues.

Updates in Issue 02 (2014-04-15) Based on Product VersionV100R007C10

This document is the second issue for product version V100R007C10. Compared with issue 01of product version V100R007C10, version 02 includes the following updates inV100R007C10SPC200:

l Optimized the description in the "Quick Reference" section.l Optimized description about the TDM capacity.


This document is the first issue for product version V100R007C10. Compared with issue 02 ofproduct version V100R007C00, version 01 of product version V100R007C10 includes thefollowing updates:



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l Updated the mapping product versions.



l Added the description that only 10GE ports support MRPS in the "Quick Reference"section.

l Deleted the specifications of originally supported 10GE single-fiber bidirectional opticalports in the "Optical Port Specifications" section.

Updates in Issue 01 (2013-04-30) Based on Product Version V100R007C00

This is the first document issue for the V100R007C00 product version. Compared with thedocument issue for the V100R006C01 product version, this issue has the following updates:

l Added MPLS-TP Ring Protection Switching (MRPS) in sections "Quick Reference" and"Network Level Protection (Packet)". (MPLS-TP is short for multiprotocol label switchingtransport profile.)

l Updated the number of FE/GE ports supported by the equipment based on the added EGS4board in sections "Quick Reference", "Access Capacities", and "Types of SupportedServices".

l Added the EGS4 board in section "Board Category".

l Added the specifications of single-fiber bidirectional optical ports in section "Optical PortSpecifications".



l Updated the number of supported FE electrical ports in sections "Quick Reference" and"Access Capacities."

l FE8F boards' support for FE electrical ports is added to sections "Types of SupportedServices" and "Board Category."


This document is the first issue for product version V100R006C01. Compared with issue 1 ofproduct version V100R006C00, this issue incorporates the following updates:

l Added the 1x10GE Ethernet processing board EX1.

l Added the 4xchannelized STM-1 service processing board CQ1.

l



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l Updated the service access capability of the equipment according to the new boards.l Optimized the structure and related description of the "Product Positioning and Features",

"Quicklook", "Networking and Application Scenarios" sections.

Updates in Issue 01 (2012-04-30) Based on Product Version V100R006C00This issue is used for first office application (FOA) of V100R006C00.



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Contents

About This Document.....................................................................................................................ii

1 Product Positioning and Features...............................................................................................11.1 Product Positioning.........................................................................................................................................................21.2 Product Features.............................................................................................................................................................2

2 Quick Reference.............................................................................................................................6

3 System Architecture and Service Access.................................................................................213.1 System Architecture.....................................................................................................................................................223.2 Service Types...............................................................................................................................................................233.2.1 Types of Supported Services.....................................................................................................................................233.2.2 Access Capacities......................................................................................................................................................25

4 Product Features...........................................................................................................................274.1 Services Supported.......................................................................................................................................................284.1.1 Service Overview (Packet)........................................................................................................................................284.1.2 Service Overview (TDM)..........................................................................................................................................344.2 Redundancy and Protection..........................................................................................................................................404.2.1 Equipment Level Protection......................................................................................................................................404.2.2 Network Level Protection (Packet)...........................................................................................................................414.2.3 Network Level Protection (TDM).............................................................................................................................564.3 Synchronization............................................................................................................................................................654.3.1 Requirements for Clock Synchronization..................................................................................................................654.3.2 Clock and Time Synchronization..............................................................................................................................66

5 Hardware and Structure.............................................................................................................765.1 Chassis..........................................................................................................................................................................775.1.1 Chassis Structure.......................................................................................................................................................775.1.2 Cross-Connect and Slot Access Capacity (Packet)...................................................................................................805.1.3 Cross-Connect and Slot Access Capacity (TDM).....................................................................................................815.2 Outdoor Cabinet...........................................................................................................................................................825.3 Board Category.............................................................................................................................................................83

6 Networking and Application Scenarios..................................................................................926.1 Basic Network Topologies...........................................................................................................................................93

OptiX OSN 550 Multi-Service CPE Optical TransmissionSystemProduct Description Contents


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6.2 Typical Application of Hybrid Networking.................................................................................................................946.3 Typical Application of Pure Packet Networking........................................................................................................1006.4 Typical Application of TDM Networking..................................................................................................................106

7 Network Management System................................................................................................1097.1 Network Management................................................................................................................................................1107.2 DCN Management......................................................................................................................................................1127.3 Synchronization Between the NMS and NEs.............................................................................................................113

8 Operation and Maintenance....................................................................................................1158.1 Maintenance Support (Packet)....................................................................................................................................1208.1.1 TP-Assist.................................................................................................................................................................1208.1.2 MPLS OAM............................................................................................................................................................1218.1.3 MPLS-TP OAM......................................................................................................................................................1228.1.4 ETH OAM...............................................................................................................................................................1228.1.5 ATM OAM..............................................................................................................................................................1248.1.6 RMON.....................................................................................................................................................................1248.1.7 PRBS.......................................................................................................................................................................1258.1.8 CES Alarm Transmission........................................................................................................................................1258.1.9 Port Mirroring..........................................................................................................................................................1278.2 Maintenance Support (TDM).....................................................................................................................................1288.2.1 PRBS.......................................................................................................................................................................1288.2.2 ETH OAM...............................................................................................................................................................1288.2.3 RMON.....................................................................................................................................................................1288.2.4 Data Test Frame.......................................................................................................................................................1288.3 Upgrade Methods.......................................................................................................................................................128

9 Security Management...............................................................................................................1309.1 Authentication Management.......................................................................................................................................1319.2 Authorization Management........................................................................................................................................1319.3 Network Security Management..................................................................................................................................1319.4 System Security Management....................................................................................................................................1339.5 Log Management........................................................................................................................................................133

10 Technical Specifications.........................................................................................................13610.1 General Specifications..............................................................................................................................................13810.2 Packet Performance Indicators.................................................................................................................................13910.3 TDM Performance Indicators...................................................................................................................................14710.4 Power Consumption and Weight of Each Board......................................................................................................15010.5 Optical Port Specifications.......................................................................................................................................15110.6 Colored Optical Ports...............................................................................................................................................16110.7 Electrical Port Specifications....................................................................................................................................16410.8 Auxiliary Port Specifications....................................................................................................................................16710.9 Indicator Status Explanation.....................................................................................................................................169



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10.10 Safety Certification.................................................................................................................................................17510.11 Environmental Specifications.................................................................................................................................17610.11.1 Storage Environment...........................................................................................................................................17610.11.2 Transportation Environment................................................................................................................................17810.11.3 Operating Environment (For the Chassis That Is Installed in a Cabinet)............................................................18110.11.4 Operating Environment (For the Chassis That Is Installed on a Wall)................................................................185

11 Energy Saving and Environmental Protection...................................................................191

12 Standard Compliance.............................................................................................................19212.1 ITU-T Recommendations.........................................................................................................................................19312.2 IETF Standards.........................................................................................................................................................19612.3 IEEE Standards.........................................................................................................................................................19912.4 Environment Related Standards...............................................................................................................................20012.5 MEF Standards.........................................................................................................................................................20112.6 Safety Standards.......................................................................................................................................................20112.7 EMC Standards.........................................................................................................................................................20212.8 Protection Standards.................................................................................................................................................204

A Glossary......................................................................................................................................205



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1 Product Positioning and Features

About This Chapter

With the increasing number of packet services, conventional time division multiplexing (TDM)devices cannot meet packet service transmission demands. The OptiX OSN 550 supports avariety of service network topologies in the TDM and packet domains, able to meet customers'various service development demands.

1.1 Product PositioningThis section describes product positioning and networking application.

1.2 Product FeaturesThis section describes the equipment features in terms of architecture and technology.

OptiX OSN 550 Multi-Service CPE Optical TransmissionSystemProduct Description 1 Product Positioning and Features


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1.1 Product PositioningThis section describes product positioning and networking application.

The OptiX OSN 550 is a packet- and TDM-oriented new-generation multi-service CPE opticaltransmission system, which is positioned at the access layer among Huawei's end-to-end Hybridmulti-service transmission platform (MSTP) product series. This system is characterized by itslarge capacity, high availability, low power consumption, and compact structure.

The OptiX OSN 550 supports multiprotocol label switching (MPLS), MPLS-transport profile(MPLS-TP), pseudo wire emulation edge-to-edge (PWE3), Ethernet, ATM, WDM, SDH, andPDH technologies. With these technologies, a pure TDM network, pure PTN network, or Hybridnetwork can be provisioned.

As the access layer equipment, the OptiX OSN 550 is networked with other OptiX OSNequipment to provide a complete solution covering the backbone layer, aggregation layer, andaccess layer. The complete solution meets 2G/3G/LTE base station backhaul and enterpriseleased service access demands. Figure 1-1 illustrates the network application of the OptiX OSN550.

Figure 1-1 Network application of the OptiX OSN 550

OptiX OSN 550 BTSNodeB BSCRNC

E1/T1

ATM/IMA E1

OptiX OSN 3500/7500 II

E1/STM-1FE

E1/FE/GE

Enterprise leased service

E1/FE/GE

ATM/IMA E1/GEE1/T1

FE

Convergence nodeAccess layerConvergence/Backbo

ne layer

1.2 Product FeaturesThis section describes the equipment features in terms of architecture and technology.



2

Large Capacity, High Availability, Low Power Consumption, and CompactStructure

The OptiX OSN 550 is access layer equipment, which features large capacity, high availability,low power consumption, and compact structure. The OptiX OSN 550 supports:

l A maximum of 60 Gbit/s packet switching capacity, a maximum of 20 Gbit/s SDH cross-connect capacity, and a maximum of four 10GE ports

l 1+1 protection for system control, switching, timing, and power supply units, and network-level protection such as tunnel APS, PW APS, Multiple Spanning Tree Protocol (MSTP),Ethernet ring protection switching (ERPS), link aggregation group (LAG), link-state passthrough (LPT), Multi-Link Point-to-Point Protocol (ML-PPP), linear multiplex sectionprotection (LMSP), MPLS-TP Ring Protection Switching (MRPS) (MPLS-TP is short formultiprotocol label switching transport profile), subnetwork connection protection(SNCP), and multiplex section protection (MSP), to improve equipment reliability

l A maximum power consumption of 300 W, a typical power consumption of only 149 Win Hybrid mode, and a typical power consumption of 67 W in TDM mode

l Dimensions (H x W x D) of 88 mm x 442 mm x 220 mm

Universal Switch Architecture and Multi-service TransmissionThe OptiX OSN 550 has a universal switch architecture, as shown in Figure 1-2. The OptiXOSN 550 supports coexistence of the time division multiplexing (TDM) domain and packettransport network (PTN) domain, which achieves smooth evolution from the TDM domain tothe PTN domain while allowing the on-demand configuration and application of pure TDMservices and packet services.

Figure 1-2 Architecture of the OptiX OSN 550

TDM Cross-connectTDM

EoS

STM-N

STM-N

TDM equipment architecture

Packet SwitchPWE3

Ethernet

Ethernet

Ethernet

Packet equipment architecture

TDM/EoS

Ethernet

PWE3

STM-N

Ethernet

“Hybrid MSTP”architecture

+

TDM Cross-connect

Packet Switch

The OptiX OSN 550 supports the access and transmission of PDH, SDH, ATM, Ethernet, MPLS,and MPLS-TP services.

In the PTN domain, the OptiX OSN 550 performs highly efficient statistical multiplexing ofdata services to reduce the service transport expenditure per bit. In the TDM domain, the OptiX



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OSN 550 incorporates SDH functions to ensure the high transport quality of Native TDMservices (mainly voice services).

End-to-End Service Configuration, One-Click Commissioning, and One-ClickFault Locating (TP-Assist)

Compared with legacy TDM networks, PTN networks have the following characteristics in termsof O&M:

l Lack of overheads indicating the physical states of networks. When a fault occurs on a PTNnetwork, no visual and fast indicator is available to locate the fault.

l Networking diversity and complication, which require powerful O&M capabilities

To address those issues, the equipment uses the TP-Assist to provide more O&M means andsimplify O&M operations for PTN networks during installation, commissioning, serviceconfiguration, fault locating, and routine maintenance. With the TP-Assist, PTN networks havethe SDH-like O&M capabilities, which reduce the technical requirements for O&M personneland improve O&M efficiency.

Hierarchical OAM

The OptiX OSN 550 supports the hierarchical OAM functions and have the SDH-like O&Mcapabilities. It can quickly detect and locate faults at each layer.

The hierarchical OAM functions include ETH OAM, MPLS tunnel/PW OAM, and MPLS-TPtunnel/PW OAM. Figure 1-3 shows the application of hierarchical OAM.

Figure 1-3 Application of hierarchical OAM

CE1

CE2

PE1

CE4

CE3

P

P

P

P

P

PE2

Ethernet Service OAM Ethernet Port OAMEthernet Port OAM

MPLS/MPLS-TP PW OAM

MPLS/MPLS-TP Tunnel OAM

ETH Layer

PW Layer

Tunnel Layer

MEP

MEP

MEP MEP

MEP

MEP

MIP MIP

OptiX OSN 550/500 OptiX OSN 3500/7500 II



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Strong Environmental Adaptabilityl The OptiX OSN 550 can be mounted in an ETSI or 19-inch cabinet, or outdoor cabinet, or

open rack, or on a wall or desk.l The OptiX OSN 550 supports the -48 V/-60 V DC power supply, 110 V/220 V AC power

supply, and uninterruptible power module (UPM) power supply. The UPM offers thestorage battery protection function and can feed 3-4 hours' power in the case of acommercial power outage.

l The OptiX OSN 550 can operate at a high temperature.Extended operating temperature: -5°C to 65°C

NOTE

Extended operating indicates that the continuous operating time of the equipment does not exceed 4hours per day and the accumulated annual operating time does not exceed 90 days.



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2 Quick Reference

This chapter describes the product overview, including product photos, hardware, software, andfunctions and features.

Table 2-1 lists the overview of the OptiX OSN 550.

Table 2-1 Overview of the OptiX OSN 550

Item Description

Appearance

Chassis dimensions (H x W x D): 88 mm x 442 mm x 220 mm

Board l System control, switching, and timing boards: CXL and PCXl Packet processing boards: CQ1, EF8F, EG4C, EM6F, EM6T, EX1, and MD1l SDH boards: SL1D, SL1Q, and SL4Dl PDH boards: PL3T and SP3Dl EoS boards: EFS8, EGS4, and EGT1l MDM board: DMD2l Auxiliary boards: AUX and FANl Power supply boards: APIU, PIU, and UPMFor services and ports supported by the preceding boards, see Table 5-4.

Packetfunctionsandfeatures

See Table 2-2.

OptiX OSN 550 Multi-Service CPE Optical TransmissionSystemProduct Description 2 Quick Reference


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Item Description

TDMfunctionsandfeatures

See Table 2-3.

Packetswitchingcapacity

60 Gbit/s

TDMcross-connectcapacity

l Higher order cross-connect capacity: 20 Gbit/sl Lower order cross-connect capacity: 5 Gbit/s

Equipment-levelprotection

l 1+1 backup for power supplyl 1+1 backup between active and standby system control, switching, and timing

boardsl Fan protection (The failure in a single fan does not affect the operation of the

other fans.)

Intelligent fanspeedadjustment

Supports the automatic adjustment of fan speed based on the highest temperatureof the board in the chassis.

Management portsandauxiliaryports

Interface Type Description Connector

External clockport

120-ohm external clockport, which can work in2048 kbit/s mode or2048 kHz mode

RJ45

External time port Two external timeinput/output ports

RJ45

Port formonitoring anoutdoor cabinet

Port for monitoring anoutdoor cabinet: Theequipment providesone port for monitoringand managing anoutdoor cabinet.

RJ45

Power supplyport

Power supply portconnecting to two-48/-60 V DC powersupplies

2 mm HM connector

Two 110 V/220 V ACpower supply ports

Three-phase socket



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Item Description

Networkmanagement port

Ethernet NM port/NMserial port, which isconnected to a networkmanagement system(NMS)

RJ45

Alarm input/output port

6-input/2-output alarmport

RJ45

64 kbit/ssynchronoustransparent dataport or 19.2 kbit/sasynchronoustransparent dataport

One 64 kbit/ssynchronous serial portor one 19.2 kbit/sasynchronous serialport, whichtransparently transmitsone channel of dataservices

RJ45

Orderwire phoneport

Used to provide voicecommunication foroperation/maintenanceengineers at differentworkstations.

RJ45

Table 2-2 OptiX OSN 550 packet functions and features

Item

Description

MPLSfunctions

The packet switching unit of the PCX board works with a service board to implementMPLS/MPLS-TP functions.l Setup mode: static tunnelsl Protection: 1:1 tunnel automatic protection switching (APS)l Operation, administration and maintenance (OAM): supports Tunnel OAM and

multiprotocol label switching transfer profile (MPLS-TP) tunnel OAM. TunnelOAM complies with ITU-T Y.1711, and MPLS-TP tunnel OAM complies withITU-T G.8113.1.



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Item

Description

PWE3functions

The packet switching unit of the PCX board works with a service board to implementPWE3 functions.l Service categories

– TDM PWE3 services (circuit emulation services [CESs])

– Asynchronous transfer mode (ATM) PWE3 services

– ETH PWE3 servicesl Setup mode: static pseudo wires (PWs)l Supports single-segment PWs (SS-PWs) and multi-segment PWs (MS-PWs).l PW encapsulation mode: Ethernet or Ethernet Tagged Model PW control word: supported by the PCXLG/PCXGA/PCXGB board whose

printed circuit board (PCB) version is Ver.B and the PCXLX/PCXX board.l Protection: 1:1 PW APSl OAM: supports MPLS PW OAM and MPLS-TP PW OAM. MPLS PW OAM

complies with ITU-T Y.1711, and MPLS-TP PW OAM complies with ITU-T G.8113.1.

Packetsystemperformance

See Table 10-2.

Service

Service Category MaximumReceivingCapability

Service Port

Description Connector

Ethernet service:l Supports the MPLS

technology.l Supports the VLAN

technology.l Supports the QinQ

technology.l Supports Native E-

Line services based onPORT, PORT+VLAN, PORT+VLAN+VLAN Pri,and PORT+QinQ.

l Supports E-Lineservices based on

FE (electricalport): 48

10/100BASE-T(X)

RJ-45

FE (opticalport): 48

l 100BASE-BX

l 100BASE-FX

l 100BASE-LX

l 100BASE-VX

l 100BASE-ZX

LC



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Item

Description

PWE3 (VPWSservices).

l Supports Native E-LAN services basedon the IEEE 802.1dbridge, IEEE 802.1qbridge, and IEEE802.1ad bridge.

l Supports E-LANservices based onPWE3 (VPLSservices).

l Supports thefollowing Ethernetdata frame formats:IEEE 802.3 andEthernet II.

l Supports jumboframes.

l Supports themaximumtransmission unit(MTU) of 960 to 9600bytes (1620 bytes bydefault).

GE (opticalport): 22

l 1000BASE-SX

l 1000BASE-LX

l 1000BASE-VX

l 1000BASE-ZX

LC

GE (electricalport): 20

1000BASE-T RJ-45

10GE (opticalports): 4

l 10GBASE-SR (LAN)

l 10GBASE-SW (WAN)

l 10GBASE-LR (LAN)

l 10GBASE-LW (WAN)

l 10GBASE-ER (LAN)

l 10GBASE-EW (WAN)

l 10GBASE-ZR (LAN)

l 10GBASE-ZW (WAN)

LC



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Item

Description

E1 service:l Service types:

– TDM PWE3 (CESE1)

– ATM PWE3

– Fractional CES E1

– ML_PPP E1l Encapsulation

formats:

– CESoPSN

– SAToPl Compression of idle

timeslots: supportedonly for CESoPSNencapsulation

l E1 coding format:HDB3

l L/M/R bit processing:supported for CESservices

l CES ACR: supported

l ATM/IMA/E1: 192xE1

l ChannelizedSTM-1:24xSTM-1

l ATM/IMA/E1: 75/120–ohm smartE1 port

l ChannelizedSTM-1:S-1.1, L-1.1,L-1.2 opticalports andSTM-1 SFPelectricalport

l ATM/IMA/E1:Anea 96

l ChannelizedSTM-1: LCoptical port andSAA straightfemale



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Item

Description

ATM/IMA service:l Supports ATM PWE3

services.l Supports ATM traffic

management.l Supports the

following ATMencapsulation modes:

– N-to-one VPC

– N-to-one VCC

– One-to-one VPC

– One-to-one VCCl Supports a maximum

of 31 concatenatedATM cells.

l Supports thefollowing ATMOAM: F4 (VP layer)and F5 (VC layer).

l Supports inversemultiplexing overATM (IMA).

192xE1 75/120-ohmsmart E1 port

Anea 96

Protection

TunnelAPS

Complies with the ITU-T Y.1720 and ITU-T G.8131 standards.l Maximum number of protection groups: 64

l Switching duration: ≤ 50 ms (for two tunnel APS protection groupswith 16 PWs per group after a link is faulty bidirectionally)

NOTE

l Tunnel APS and PW APS share 64 protection group resources.

l MPLS tunnel APS and MPLS-TP tunnel APS share 64 protection groupresources.

PW APS Complies with the ITU-T Y.1720 and ITU-T G.8131 standards.l Maximum number of protection groups: 64l Maximum number of members bound into a PW: 512

l Switching duration: ≤ 50 ms (for a protection pair that contains eightmembers or six PW APS protection groups after a link is faultybidirectionally)

NOTE

l Tunnel APS and PW APS share 64 protection group resources.

l MPLS PW APS and MPLS-TP PW APS share 64 protection group resources.



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Item

Description

MRPS Supports coexistence of MRPS rings and tunnel APS. ETH PWE3services on the MRPS rings do not support the PW control word mode.MRPS is implemented based on ITU-T G.8132.l Number of rings: 4l Number of nodes per ring: 64l Number of virtual nodes per ring: 32l Number of multicast services supported by a ring node: 16l Number of multicast services supported per ring: 8NOTE

Only 10GE ports support MRPS.

The number of nodes per ring is the number of physical nodes on the ring.

The number of virtual nodes per ring is the number of virtual intersecting nodesthat are created to contain the two most remote physical interconnecting nodes onthe ring. When a ring intersects with multiple rings, the virtual intersecting nodemust be created to contain the two most remote physical intersecting nodes on thering and each other ring.

MSTP Complies with the IEEE 802.1s standard.l Maximum number of instances per port: 1l Maximum number of port groups: 1l Maximum number of ports provided by all port groups: 16

ERPS Supports ERPS that complies with ITU-T G.8032 and ITU-T Y.1344.l Maximum number of protection groups: 8

l Switching duration: ≤ 50 ms at an optical port and ≤ 2s at anelectrical port if the number of nodes on a ring network is not morethan 16 and the link is faulty bidirectionally

NOTEOnly Native ETH services support ERPS.

LPT Complies with the Huawei proprietary protocol.l Maximum number of services that support LPT: 16l Point-point and point-multipoint LPTl Switching duration:

– ≤ 300 ms if the fault is on the NNI side and is detected using PWOAM

– ≤ 300 ms at an optical port and ≤ 3s at an electrical port if thefault is on the UNI side



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Item

Description

LAG Complies with the IEEE 802.3ad and IEEE 802.1AX standards.l LAG protectionl A maximum of 16 LAGs. Each LAG has a maximum of eight

members.l Switching duration:

– Manual/Static LAG: ≤ 50 ms at an optical port and ≤ 2s at anelectrical port if the link is interrupted bidirectionally

– Static LAG: ≤ 3s if the link is interrupted unidirectionally

ML-PPP Complies with the IETF RFC 1661 and IETF RFC 1990 standards.l Total number of PPP links: 504l Number of ML-PPP groups: 64l Number of member links in an ML-PPP group: 16

LMSP Complies with the ITU-T G.841 and ITU-T G.842 standards.l Number of protection groups: 8

l Protection switching time: ≤ 50 ms

Maintenance

MPLS/MPLS-TPOAM

Complies with the ITU-T Y.1711 and ITU-T G.8113.1 standards.l Tunnel OAM and PW OAMl MPLS OAM: supports CV, FFD, BDI, FDI, Ping, and Traceroute.l MPLS-TP OAM: supports CC, RDI, AIS, LB, LT, PW LM, LCK,

TST (packet loss test only), PW CSF, and two-way DM.l Maximum sum of the number of tunnels supporting OAM and the

number of PWs supporting OAM: 128NOTE

MPLS tunnel OAM, MPLS PW OAM, MPLS-TP tunnel OAM, MPLS-TP PWOAM, ETH OAM, and MRPS OAM (one MRPS ring uses two OAM resources)share resources.



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Item

Description

ETHOAM

Complies with the IEEE 802.3ah and IEEE 802.1ag standards.l Ethernet service OAM: supports continuity check (CC), loopback

(LB), linktrace (LT), alarm indication signal (AIS), lossmeasurement (LM), and delay measurement (DM).

l Ethernet port OAM: supports OAM auto-discovery, linkperformance monitoring, fault detection, remote loopback, and self-loop detection and looped-port blocking.

l Maximum number of MDs/MAs/MEP/MIPs: 64NOTE

l MPLS tunnel OAM, MPLS PW OAM, MPLS-TP tunnel OAM, MPLS-TPPW OAM, ETH OAM, and MRPS OAM (one MRPS ring uses two OAMresources) share resources.

l Only the E-Line service transmitted in native Ethernet mode supports ETH-LM and ETH-DM.

l LM/DM are based on IEEE 802.1ag, implemented by referring to the ITU-TY.1731 standard.

MRPSOAM

Complies with the ITU-T G.8113.1 standard.Supports CC and RDI.NOTE

MPLS tunnel OAM, MPLS PW OAM, MPLS-TP tunnel OAM, MPLS-TP PWOAM, ETH OAM, and MRPS OAM (one MRPS ring uses two OAM resources)share resources.

ATMOAM

Supports the following ATM OAM functions: CC, LB, RDI, and AIS.

RMON Supports port-level and service-level RMON functions, in compliancewith RFC 1757 and RFC 2819. Supports four RMON managementgroups: Ethernet statistics group, Ethernet history group, and Ethernethistory control group.Port level:l Basic Ethernet performancel Extended Ethernet performanceService level:l L2VPN (private line service)l Transit tunnell PW

SNMP Queries port information and port/service performance statistics usinga standard SNMP terminal.



15

Item

Description

Portmirroring

Supports port mirroring that enables Ethernet service analysis andservice fault diagnosis without affecting the services.l Supports local port mirroring.l Supports mirroring in the egress direction of a UNI port.l Supports mirroring in the ingress direction of UNI and NNI ports.l Supports mirroring of PORT+VLAN services in the ingress direction

of a UNI port.

Synchronization

SynchronousEthernet

l Synchronous Ethernet clock that complies with ITU-T G.8261 andITU-T G.8262.

l Port receiving/transmitting synchronous Ethernet clocks: FE/GE/10GE

l Clock source selection algorithm based on the synchronization statusmessage (SSM) protocol

l Clock frequency stability (holdover mode): < 50 ppbNOTE

SFP electrical modules do not support synchronous Ethernet clocks.

When working in 10BASE-T mode, FE/GE ports do not support synchronousEthernet clocks.

IEEE1588v2

l Supports the OC, BC, TC, and BC+TC clock models. The TC modelcan work in two modes: E2E TC and P2P TC.

l Supports the delay deviation compensation for line transmission intwo modes: length deviation compensation and time deviationcompensation. The length deviation compensation value ranges from0 m to 12000 m, and the time deviation compensation value rangesfrom 0 ns to 65535 ns.

l Supports two 1PPS+ToD or DCLS external time ports, which usethe RS-422 level. Each port supports compensation for propagationdelay on its connected cable. The compensation can be set to a valueranging from 0 μs to 10 μs in steps of 10 ns or less. ToD supportscyclic redundancy checks (CRCs).

l Supports the setting of the input/output mode at time ports.NOTE

A port in 10GE WAN mode does not support IEEE 1588v2.

IEEE 1588ACR

l The IEEE 1588 ACR slave recovers synchronous clocks from IEEE1588 packets.

l The quality level of IEEE 1588 ACR clocks can be converted intothat of synchronous Ethernet clocks.

NOTEA port in 10GE WAN mode does not support IEEE 1588 ACR.



16

Item

Description

CES ACR l Supports the clock recovery function in absolute mode.l Maximum number of CES ACR clocks: 24l The clock performance complies with the ITU-T G.823 Traffic

template.

Others

QoS l DiffServSupports simple traffic classification by specifying PHB serviceclasses for service flows based on their QoS information (C-VLANpriorities, S-VLAN priorities, DSCP values, or MPLS EXP values)carried by packets.

l Complex traffic classificationSupports complex traffic classification based on C-VLAN IDs, S-VLAN IDs, C-VLAN priorities, S-VLAN priorities, C-VLAN IDs+ C-VLAN priorities, S-VLAN IDs + S-VLAN priorities, or DSCPvalues carried by packets, and V-UNI ingress policies.

l QoS policiesSupports port policies and V-UNI ingress policies.

l Access control list (ACL) policyPasses or discards packets in a flow that matches rules specified bya port policy or V-UNI ingress policy.

l CARProvides the CAR function for traffic flows at ports and V-UNIingresses.

l ShapingProvides traffic shaping for a specific port, PW ingress, prioritizedqueue, or traffic flow.

l Congestion managementSupports tail drop and WRED dropping.

l Queue scheduling policiesSupports SP, WRR, and SP+WRR.

Table 2-3 OptiX OSN 550 TDM functions and features

Item Description

Service Service Category MaximumReceivingCapability

Service Port




17

Item Description

SDH service 26xSTM-1 l S-1.1,L-1.1, andL-1.2opticalports

l STM-1SFPelectricalports

l Opticalport: LC

l Electricalport: SAAstraightfemale

14xSTM-4 S-4.1, L-4.1and L-4.2optical ports

LC


LC

PDH service 252xE1/T1 E1 (75/120-ohm)/T1(100-ohm)electricalports

Anea 96

18xE3/T3 E3 (75-ohm)/T3 (75-ohm)electricalports

SMB

Ethernet service:l Ethernet private line

(EPL) servicesl Ethernet virtual private

line (EVPL) servicesl Ethernet private LAN

(EPLAN) services(based on the IEEE802.1d bridge)

l Ethernet virtual privateLAN (EVPLAN)services (based on theIEEE 802.1q and802.1ad bridges)

l FE opticalport: 24

l FEelectricalport: 48

l FE opticalport:100BASE-BX,100BASE-FX,100BASE-LX,100BASE-VX, and100BASE-ZX

l FEelectricalport:10/100BASE-T(X)

l Opticalport: LC

l Electricalport: RJ45



18

Item Description

24xGE l GE opticalport:1000BASE-SX/LX/VX/ZX

l GEelectricalport:1000BASE-T

l Opticalport: LC


TDMnetwork-levelprotection

SNCP l SNCP at the VC-12, VC-3, and VC-4 levelsl Maximum number of protection groups: 1032

l Switching duration: ≤ 50 ms

Ring MSP l Ring MSP at the STM-1, STM-4 and STM-16 levelsl Maximum number of protection groups: 13


Linear MSP l Linear MSP at the STM-1, STM-4 and STM-16 levelsl Maximum number of 1+1/1:1 linear MSP protection

groups: 13


Maintenance

PRBS Supported

Portmirroring

EFS8/EGS4 supports port mirroring that enables Ethernetservice testing and service fault diagnosis without affecting theservices.l Supports local port mirroring.l Supports ingress and egress port mirroring.

Synchronization

Physicallayer clocks

l Including external clocks, line clocks, tributary clocks, andinternal clocks. The port impedance is 120 ohms or 75 ohms(a converter can be used to provide a 75-ohm clock port).

l Non-synchronization status message (SSM), standardSSM, and extended SSM protocols

l Tributary retiming of tributary clocksl Locked mode, holdover mode, and free-run mode



19

Item Description

SynchronousEthernet

EGS4 supports synchronous Ethernet clocks.l Synchronous Ethernet clock that complies with ITU-T G.

8261 and ITU-T G.8262.l Port receiving/transmitting synchronous Ethernet clocks:

FE/GEl Clock source selection algorithm based on the

synchronization status message (SSM) protocoll Clock frequency stability (trace mode): < 50 ppbNOTE




20

3 System Architecture and Service Access

About This Chapter

The chapter describes the equipment's system architecture and service access.

3.1 System ArchitectureThe OptiX OSN 550 is a dual-domain (time division multiplexing [TDM] and packet domains)device. This section describes its functional units and the relationship between these units.

3.2 Service TypesThis section describes the maximum service access capabilities, service ports, and boardsproviding specific service types for the OptiX OSN 550.

OptiX OSN 550 Multi-Service CPE Optical TransmissionSystemProduct Description 3 System Architecture and Service Access


21

3.1 System ArchitectureThe OptiX OSN 550 is a dual-domain (time division multiplexing [TDM] and packet domains)device. This section describes its functional units and the relationship between these units.

The OptiX OSN 550 consists of the following functional units: service interface unit, TDMcross-connect unit, packet switching unit, system control and communication unit, clock unit,auxiliary interface unit, fan unit, and power supply unit.

Figure 3-1 System architecture of OptiX OSN 550

Synchronous/Asynchronous dataExternal alarm

System control and communication unit

-48 V/-60 V DC

Orderwire

Ethernet signal

VC-4 signal

Packet service External clock

110 V/220 V AC

TDM service

Service interface

unit

TDM cross-

connect unit

Packet switching

unit

NMS

DCN

Clock unit

Fan unit

Power supply

unit

Control and communication bus & Clock bus

Cross-connect busOptical/Electrical service

Auxiliary interface

unit

Backplane



22

Table 3-1 Function units of the OptiX OSN 550

Function Unit Function

Service interfaceunit

Packet services:l Receives/Transmits TDM E1/channelized STM-1 signals.l Receives/Transmits ATM/inverse multiplexing over ATM (IMA)

E1 signals.l Receives/Transmits FE/GE/10GE signals.TDM services:l Receives/Transmits E1/T1/E3/T3 signals.l Receives/Transmits STM-1/4/16 signals.l Receives/Transmits FE/GE signals.

TDM cross-connectunit

l Provides the cross-connect function and grooms TDM services.

Packet switchingunit

l Processes Ethernet services and forwards packets.l Processes MPLS labels and forwards packets.l Processes PW labels and forwards packets.

System control andcommunication unit

l Performs system communication and control.l Configures and manages the system.l Collects alarms and monitors performance.l Processes overhead bytes.

Clock unit l Traces clock sources and provides clock signals for the system.l Provides the input/output port for external clocks.

Auxiliary interfaceunit

l Provides the orderwire phone port.l Provides the synchronous/asynchronous data port.l Provides the external alarm input/output port.

Power supply unit l Connects to -48 V/-60 V DC power supplies.l Connects to 110 V to 220 V AC power supplies.

Fan unit l Cools the NE.

3.2 Service TypesThis section describes the maximum service access capabilities, service ports, and boardsproviding specific service types for the OptiX OSN 550.

3.2.1 Types of Supported ServicesDifferent boards providing a wide variety of service ports can be deployed on the OptiX OSN550.



23

Table 3-2 lists the services supported by the OptiX OSN 550.

Table 3-2 Types of supported services

ServiceCategory

ServiceType

ServiceRate

Board Reference Standard

Packet

10 GE LANservice

10.31 Gbit/s PCXLX/PCXX/EX1 IEEE 802.3ae

10 GEWANservice

9.95 Gbit/s PCXLX/PCXX/EX1

GE service(opticalport)

1000 Mbit/s PCXLG/PCXGA/PCXGB/EM6F/EG4C

IEEE 802.3z

GE service(electricalport)

1000 Mbit/s EM6T/EM6F/EG4C

FE service(opticalport)

100 Mbit/s EF8F/EM6F/EG4C IEEE 802.3u

FE service(electricalport)

10/100Mbit/s

EF8F/EM6T/EM6F

ATM/IMA/E1 CESservice

2.048 Mbit/s

MD1 ITU-T G.703ITU-T G.823

Channelized STM-1CES service

155.52Mbit/s

CQ1 ITU-T G.957ITU-T G.703

SDH STM-1standardservice

155.52Mbit/s

SL1D/SL1Q/PCXLX/PCXLG/CXL1

ITU-T G.707ITU-T G.691ITU-T G.957ITU-T G.693ITU-T G.783ITU-T G.825

STM-4standard orconcatenation service

622.08Mbit/s

SL4D/PCXLX/PCXLG/CXL4

STM-16standard orconcatenation service

2.5 Gbit/s PCXLX/PCXLG/CXL16



24

ServiceCategory

ServiceType

ServiceRate

Board Reference Standard

PDH E1 service 2.048 Mbit/s

SP3D ITU-T G.703ITU-T G.823ITU-T G.783ITU-T G.824ITU-T G.742

T1 service 1.544 Mbit/s

SP3D ITU-T G.703ITU-T G.823ITU-T G.824ITU-T G.783

T3 service 44.736Mbit/s

PL3T ITU-T G.703ITU-T G.824

E3 service 34.368Mbit/s

PL3T ITU-T G.703ITU-T G.823

EoS FE service 10/100Mbit/s

EFS8/EGS4 IEEE 802.3u

GE service 1000 Mbit/s EGT1/EGS4 IEEE 802.3z

FE: Fast EthernetGE: Gigabit Ethernet

3.2.2 Access CapacitiesThis section describes access capacities when different system control, switching, and timingboards are configured in the OptiX OSN 550.

Access Capacity in Packet Mode

Table 3-3 lists access capacities in packet mode when different system control, switching, andtiming boards are configured on the OptiX OSN 550.

Table 3-3 Access capacities of the OptiX OSN 550 in packet mode

Board 10GE(Optical Port)

GE(Optical Port)

GE(Electrical Port)

FE(Optical Port)

FE(Electrical Port)

ATM/IMA/E1CES

ChannelizedSTM-1CES

PCXLX 4 20 20 48 48 192 24



25

Board 10GE(Optical Port)

GE(Optical Port)

GE(Electrical Port)

FE(Optical Port)

FE(Electrical Port)

ATM/IMA/E1CES

ChannelizedSTM-1CES

PCXX 4 20 20 48 48 192 24

PCXLG 2 22 20 48 48 192 24

PCXGA 0 22 20 48 48 192 24

PCXGB 2 22 20 48 48 192 24

Access Capacity in TDM ModeTable 3-4 lists access capacities in TDM mode when different system control, switching, andtiming boards are configured on the OptiX OSN 550.

Table 3-4 Access capacities of the OptiX OSN 550 in TDM mode

Board STM-1 STM-4 STM-16

E1/T1 E3/T3 FE(OpticalPort)

FE(ElectricalPort)

GE

PCXLX

26 14 2 252 18 24 48 24

PCXX 24 12 0 252 18 24 48 24

PCXLG

26 14 2 252 18 24 48 24

PCXGA

24 12 0 252 18 24 48 24

PCXGB

24 12 0 252 18 24 48 24

CXL1 26 12 0 252 18 24 48 24

CXL4 24 14 0 252 18 24 48 24

CXL16 24 12 2 252 18 24 48 24



26

4 Product Features

About This Chapter

This chapter describes equipment features in terms of available service types, protection, andsynchronization.

4.1 Services SupportedThe OptiX OSN 550 supports Ethernet services, ATM/IMA/E1 services, channelized STM-1,EoS services, SDH services, and PDH services.

4.2 Redundancy and ProtectionThe OptiX OSN 550 supports multiple redundancy and protection schemes.

4.3 SynchronizationThe OptiX OSN 550 supports IEEE 1588v2, synchronous Ethernet clock, 2 MHz, and 2 Mbit/s clocks and can provide an end-to-end clock transport solution when deployed with MSTP orPTN products.

OptiX OSN 550 Multi-Service CPE Optical TransmissionSystemProduct Description 4 Product Features


27

4.1 Services SupportedThe OptiX OSN 550 supports Ethernet services, ATM/IMA/E1 services, channelized STM-1,EoS services, SDH services, and PDH services.

4.1.1 Service Overview (Packet)This section describes the packet service types supported by the equipment.

Ethernet Services (E-Line and E-LAN)The OptiX OSN 550 supports point-to-point E-Line services and multipoint-to-multipoint E-LAN services.

Standardization organizations such as ITU-T, IETF and MEF stipulate the model frames for L2Ethernet services. Table 4-1 lists these model frames. In this document, the L2 Ethernet servicesare of the model frame stipulated by MEF.

Table 4-1 Comparison among L2 Ethernet services stipulation

Service Type ServiceMultiplexing

TransportTunnel

IETFModel

ITU-TModel

MEFModel

Point-to-pointservice

Line Physicallyisolated

Physicallyisolated

- EPL E-Line

VirtualLine

VLAN VLAN - EVPL

MPLS VPWS

Multipoint-to-multipointservice

LAN Physicallyisolated

Physicallyisolated

- EPLAN E-LAN

VirtualLAN

VLAN Physicallyisolated

- EVPLAN

VLAN -

MPLS VPLS

Table 4-2 lists the E-Line and E-LAN services supported by the OptiX OSN 550.



28

Table 4-2 E-Line and E-LAN services supported by the OptiX OSN 550

Service Service Type

E-Line Native Ethernetservices

Point-to-point transparently transmitted E-Line service

VLAN-based E-Line services

QinQ-based E-Line services

ETH PWE3services

E-Line services carried by PWs (VPWS services)

E-LAN Native Ethernetservices

E-LAN services based on IEEE 802.1d bridges

E-LAN services based on IEEE 802.1q bridges

E-LAN services based on IEEE 802.1ad bridges

ETH PWE3services

E-LAN services carried by PWs (VPLS services)

E-Line ServiceFigure 4-1 illustrates the E-Line service provided by the OptiX OSN equipment.

Company A has two branches in City 1 and City 3. Company B has two branches in City 2 andCity 3. Company C has two branches in City 1 and City 2. The branches of Companies A, B,and C require data communication. The OptiX OSN equipment can separately provide a privateline service for Companies A, B, and C to meet the communication requirement. In addition,the service data is completely isolated.

Figure 4-1 E-Line service

Nationwide/Globalcarrier Ethernet Metro

carrier EthernetMetro

carrier Ethernet

Metrocarrier Ethernet

Company A

City 3City 1

Company A

E-Line1E-Line2E-Line3

Company C Company B

Company C Company B

City 2



29

E-LAN ServiceFigure 4-2 illustrates the E-LAN service provided by the OptiX OSN equipment.

Company Z is headquartered in City 3. Branch A of the company is located in City 1 and City2, and Branch B of the company is located in City 1, City 2, and City 3. Branch A and BranchB do not communicate with each other, and the data of them should be separated from eachother. The headquarters, however, need to communicate with all the branches and need to accessthe Internet.

The OptiX OSN equipment can be used to provide the E-LAN service. Different VLAN tagsare used to identify service data from different branches. In this manner, the headquarters cancommunicate with the branches and the data from different branches is isolated. In addition, theVLAN is used to isolate the Internet data accessed by the headquarters from the internal servicedata.

Figure 4-2 E-LAN service

Nationwide/Globalcarrier Ethernet




Headquarter

Branch B

City 3

Branch A

City 1

Branch B

Branch A

City 2VLAN1VLAN2

Branch B Branch A

ISP

VLAN3

CES ServicesThe circuit emulation service (CES) helps to solve the problem of insufficient optical fiberresources in the access ring and allows TDM services to be transparently transmitted across thepure packet mode.

At the physical layer on the UNI side, the OptiX OSN equipment is interconnected with a CEthrough the following physical channels for accessing CES services:



30

l Channelized STM-1

l E1

Figure 4-3 Networking diagram of the CES

PSN

PE1 PE2CE1 CE2

AC AC

(BTS) (BSC)

LSP

Native TDMservice TDM PWE3

Framed E1----

Idle TSService TS

Packet transmission equipment

PW

Framed E1 TDM PWE3 packet

Native TDMservice

Emulation Mode

The OptiX NG-SDH series equipment supports two types of CES services: structure-aware TDMcircuit emulation service over packet switched network (CESoPSN) CES and structure-agnosticTDM over packet (SAToP) CES.

In the case of CESoPSN CES:

l The equipment senses the frame format, frame alignment mode, and timeslot informationin the TDM circuit.

l The equipment processes the overheads and extracts the payloads in TDM frames. Then,the equipment loads timeslots to the packet payload in a certain sequence. As a result, theservices in each timeslot are fixed and visible in packets.

In the case of SAToP CES:

l The equipment does not sense any format in the TDM signal. Instead, it considers TDMsignals as bit flows at a constant rate, and therefore the entire bandwidth of TDM signalsis emulated.

l The overheads and payloads in TDM signals are transparently transmitted.

Service Type

CES services are classified into UNI-UNI CES services and UNI-UNI CES services by serviceimplementation point.

l UNI-UNI CES services

As shown in Figure 4-4, a single OptiX OSN NE completes access of TDM services.



31

Figure 4-4 UNI-UNI CES services

BTS

BSC

TDM link

NE

PSN

l UNI-NNI CES services

As shown in Figure 4-5, the OptiX OSN NEs set UNI-NNI CES services. In the case of aUNI-NNI CES service, the OptiX OSN NEs access customer TDM services through E1ports; CES PWs are created between the OptiX OSN NEs to emulate end-to-end TDMservices.

Figure 4-5 UNI-NNI CES services

BTS2

BSC

BTS1

TDM link

NE

NE

NE

PSN

Tunnel

PW

ATM/IMA Services

The OptiX OSN equipment supports ATM/IMA services in packet mode.

ATM Services

ATM stands for asynchronous transfer mode, which is implemented based on cells. In ATMmode, the ATM PWE3 technology is used to emulate ATM services on a packet switched



32

network (PSN). Therefore, traditional ATM services can traverse the PSN. ATM servicenetworks can be classified into three types: one-to-one, N-to-one or ATM-TRANS, accordingto the encapsulation mode of ATM PWE3 packets.

Figure 4-6 Typical application of ATM PWE3 (in one-to-one cell encapsulation mode)

PSN

PE1 PE2


1-to-1 ATMPWE3service

ATM PWE3

LSP

PW

AC AC

CE2CE1

NodeB RNC

1-to-1 ATMPWE3service

Figure 4-7 Typical application of ATM PWE3 (in N-to-one cell encapsulation mode)

PSN

PE1 PE2


N-to-1 ATMPWE3service

ATM PWE3

LSP

PW

AC AC

CE4CE2

CE1

CE3

NodeB RNC

N-to-1 ATMPWE3service



33

NOTE

The cell encapsulation modes at both ends of a PW must be the same.

IMA Services

The inverse multiplexing for ATM (IMA) technology multiplexes multiple low-speed ATMlinks into a high-speed link.

The IMA technology provides inverse multiplexing of an ATM cell stream over multiple low-speed links and retrieves the original stream at the far-end from these physical links. Figure4-8 shows how IMA transmits services.

Figure 4-8 IMA transmission

Link 1

Link 2

Link 3

IMA group

ATM cell stream ATM cell stream

The IMA technology helps to group multiple physical links to form a higher bandwidth logicallink whose rate is approximately the sum of the link rates. When the member links in the IMAgroup are dynamically added/deleted, or fail/recover, the logical link changes only in bandwidth.The services on the logical link are not interrupted only when the bandwidth of the logical linkis not lower than the required minimum bandwidth.

With the IMA technology, the transport network can transmit ATM services from customerequipment on an IMA group formed by multiple low-speed links (for example, the three E1 linksshown in Figure 4-9), therefore increasing link bandwidth utilization and providing linkprotection.

Figure 4-9 Application of the IMA technology

IMA group

NodeBE1 link

Packet transmit equipment

4.1.2 Service Overview (TDM)This section describes the TDM service types supported by the equipment.



34

Ethernet Services (EPL/EVPL/EPLAN/EVPLAN)ETH OAM enhances Ethernet Layer 2 maintenance functions and it strongly supports servicecontinuity verification, service deployment commissioning, and network fault locating.

The OptiX OSN equipment supports the following types of Ethernet services:

l EPL Servicel EVPL Servicel EPLAN Servicel EVPLAN Service

EPL ServiceThe EPL implements the point-to-point transparent transmission of Ethernet services. As shownin Figure 4-10, the Ethernet services of different NEs are transmitted to the destination nodethrough their respective VCTRUNKs. The Ethernet services are also protected by the SDH self-healing ring (SHR). This ensures the secure and reliable transmission of services.

Figure 4-10 EPL service based on port

VCTRUNK 1PORT1

PORT2

VCTRUNK 1

VCTRUNK2 VCTRUNK2

POTR1

A

NE 1 NE 2

BPORT2

OptiX OSNequipment

Enterpriseuser

A

B

EVPL ServiceThe OptiX OSN equipment adopts two ways to support EVPL services.

l Port-shared EVPL services. The services are isolated by VLAN tags and share a bandwidth.

As shown in Figure 4-11, traffic classification is performed for the Ethernet service accordingto VLAN ID, to distinguish different VLANs from different departments of Company A. Thetwo traffics are transmitted in respective VCTRUNKs.



35

Figure 4-11 Port-shared EVPL servicesHeadquarters of

company A

OptiX OSNequipment

Enterpriseuser

NE 1 NE 2

PORT1

PORT2

VLAN100

PORT1

VLAN100

VLAN200 VLAN200

VCTRUNK1

VCTRUNK2

Department 1

Department 2

l VCTRUNK-shared EVPL services. OptiX OSN equipment adopts three ways to realize

convergence and distribution of EVPL services.

– EVPL services based on VLAN ID, as shown in Figure 4-12.

– EVPL services based on MPLS, as shown in Figure 4-13.

– EVPL services based on QinQ, as shown in Figure 4-14.

Figure 4-12 EVPL service based on VLAN ID

Communityuser

Cyber cafeuser

OptiX OSNequipment

VCTRUNK

AA'

NE 1 NE 2

B

VLAN100

VLAN200

VLAN100

VLAN200

1 PORT2 1PORT PORTPORT2

B'



36

Figure 4-13 EVPL service based on MPLS

NE 1 NE 2

PPE P PE

VCTRUNK1

PORT2

PORT1PORT1

PORT2

`

Add label

Department B

DepartmentA

Branch 1

Company A OptiX OSNequipment

Strip label

Branch 2

Department B

Department A

Figure 4-14 EVPL service based on QinQ

Department B

Department A

NE 1 NE 2

VCTRUNK1

PORT2

PORT1PORT1

PORT2

`

C-Aware S-Aware S-Aware C-Aware

Company A OptiX OSN equipment

Add label Strip label

Branch 1 Branch 2

Department B

Department A

EPLAN ServiceThrough the EPLAN service, NEs can communicate with each other and dynamically share abandwidth, the OptiX OSN equipment adopts virtual bridge (VB) to support Layer 2 switchingof Ethernet data. This is referred to as the EPLAN service.

Each NE in the system can create one or several VBs. Each VB establishes a media access control(MAC) address table. The system updates the table by self-learning. The data packets aretransmitted over the mapping VCTRUNK according to the destination MAC address, as shownin Figure 4-15.



37

Figure 4-15 EPLAN service

NE 1 NE 2

NE31

VCTRUNK1

VCTRUNK2

VCTRUNK1

PORT1

VCTRUNK1

PORT1PORT1 VB

VB

VB

Port 1

Department 3 ofcompany A

Port 1


Accesspoint

Company A OptiX OSNequipment

Port 1


EVPLAN ServiceThe EVPLAN services can dynamically share the bandwidth and the data packets in the sameVLAN are isolated from each other. When the data services with the same VLAN ID are accessedinto the same NE and dynamically share the bandwidth, the EVPLAN service can meet theservice requirements.

As shown in Figure 4-16, the Ethernet processing boards of the OptiX OSN equipment adoptVB+S-VLAN filter table to support the EVPLAN services.



38

Figure 4-16 EVPLAN service

NE 1 NE 2

NE3

PORT1PORT2

VCTRUNK1VCTRUNK2

LSP LSP PORT1PORT2

VC

TRU

NK

1

PO

RT1

PO

RT2 V

CTR

UN

K2

S-Aware S-Aware

S-Aware

C-AwareS-Aware

C-Aware

VB

VB

VB

Port 1

Department 3 of company B

Department 3 of company A

Port 2

Port 1

Port 1

Port 2

Department 2 of company B Department 2

of company A Department 1 of company B

Department 1 of company A

Acess point Company A Company B OptiX OSN

equipment

Port 2

C-Aware

SDH/PDH ServiceThis section describes the service support in TDM mode.

The OptiX OSN 550 can process SDH services and PDH services. Table 4-3 lists the servicecategories that the OptiX OSN 550 supports in TDM mode.

Table 4-3 Service categories that the OptiX OSN 550 supports in TDM mode

ServiceCategory

Description

SDH service l Standard SDH services: STM-1/STM-4/STM-16l Standard SDH concatenated services: VC-4-4c/VC-4-16c

l Standard SDH virtual concatenation services: VC-4-Xv (X≤8),VC-3-Xv (X≤24), VC-12-Xv (X≤63)

PDH service E1/T1 and E3/T3 services



39

4.2 Redundancy and ProtectionThe OptiX OSN 550 supports multiple redundancy and protection schemes.

4.2.1 Equipment Level ProtectionThe equipment supports several equipment level protection schemes.

Power Redundancy

1+1 backup for power supply: two channels of -48 V DC power supplies are connected by usingtwo PIU boards for backup.

As shown in Figure 4-17, the OptiX OSN 550 is configured with a pair of DC power suppliesfor backup. Normal operations are not affected if any external -48 V DC power supply fails.

Figure 4-17 DC power redundancy for the OptiX OSN 550 chassis

SLOT 1 SLOT 2

SLOT 3 SLOT 4

SLOT 5 SLOT 6

SLOT 7 SLOT 8

PIU

PIU

FAN

XXX

XXX

XX

XXX

XX

XXX

XX

XXXX

XX

XX

XX

XX

XX

Mutual backup DC input

As shown in Figure 4-18, the OptiX OSN 550 is configured with a pair of AC power suppliesfor backup. Normal operations are not affected if any external 100 V/240 V AC power supplyfails.

Figure 4-18 AC power redundancy for the OptiX OSN 550 chassis

SLOT 1

SLOT 3

SLOT 5 SLOT 6

SLOT 7 SLOT 8

SLO

T91

SLO

T 92

SLO

T 93

XXXX

XXXX

XXXX

XXXX

XXXX

XXXX

APIU APIU

Mutual backup AC input

System Control, Switching, and Timing Board Redundancy

The equipment provides 1+1 backup between the active and standby system control, switching,and timing boards.



40

Figure 4-19 Board redundancy for the OptiX OSN 550 chassis (system control, switching, andtiming board)

SLOT 1 SLOT 2

SLOT 3 SLOT 4

SLOT 5 SLOT 6

SLOT 7 SLOT 8PI

UPI

U

FAN

XXXX

XXXX

XXXX

XXXX

XXXX

XXXX

XXXX

XXXX

1+1 backup between active and standby

Fan Redundancy

Six air-cooling fans dissipate the heat generated by the system. The failure of a single fan doesnot affect the operation of other fans.

4.2.2 Network Level Protection (Packet)This section describes packet domain protection schemes.

PW APS

This section defines PW APS and describes its purpose.

Definition

PW APS is a function that protects PWs based on the APS protocol. When the working PW isfaulty, PW APS switches services to a preconfigured protection PW.

The PW APS function supported by the OptiX OSN equipment has the following features:

l End-to-end protection for PWs.

l The working PW and protection PW are carried in different tunnels but have the same localand remote PEs.

l The protection PW in the PW APS protection pair does not carry extra traffic.

l The PW OAM (based on ITU-T Y.1711) or MPLS-TP OAM (based on ITU-T G.8113.1)mechanism is used to detect faults in PWs, and the ingress and egress nodes exchange APSprotocol packets to achieve protection switching.

Purpose

PW APS improves the reliability of service transmission in PWs.

As shown in Figure 4-20, when the PW OAM mechanism detects a fault in the working PW,services are switched to the protection PW for transmission.



41

Figure 4-20 Example of PW APS

PE1

PE2

PE3

Protect switching

PE1 PE4

PE2

PE3Service

Working PW

Protection PW

Working PW

Protection PW


PE4

Tunnel APS

This section defines tunnel APS and describes the purpose of using this feature.

Definition

Tunnel APS is a function that protects tunnels based on the APS protocol. When the workingtunnel is faulty, tunnel APS switches services to a preconfigured protection tunnel.

Tunnel APS supported by the OptiX OSN equipment has the following features:

l Provides end-to-end protection for tunnels.

l The working tunnel and protection tunnel have the same ingress and egress nodes.



42

l The protection tunnel in the Tunnel APS protection pair does not carry extra traffic.l The MPLS OAM (based on ITU-T Y.1711) or MPLS-TP OAM (based on ITU-T G.8113.1)

mechanism is used to detect faults in tunnels, and the ingress and egress nodes exchangeAPS protocol packets to achieve protection switching.

PurposeTunnel APS is used to improve the reliability of service transmission over tunnels. Tunnel APSis used in two typical scenarios: co-sourced and co-sinked tunnels, and co-sourced tunnels withdifferent sinks. Figure 4-21 and Figure 4-22 show the typical application scenarios.

For co-sourced and co-sinked tunnels, a tunnel APS protection group is created between PE1and PE2. Generally, services are transmitted on the working tunnel. When the working tunnelis faulty, APS occurs and the services are switched to the protection tunnel.

Figure 4-21 Typical application of tunnel APS (for co-sourced and co-sinked tunnels)

NodeB

RNCPE1

Tunnel APS

PE2

NodeB

Tunnel1

PSNTunnel APS

Tunnel2

Working Tunnel

Protection Tunnel

For co-sourced tunnels with different sinks, tunnel APS works with MC-LAG to implementcross-equipment protection. As shown in Figure 4-22, PE1 is an access-layer NE, and PE2 andPE3 are NEs at the backbone convergence layer. A tunnel APS protection group is createdbetween PE1 and PE2 and between PE1 and PE3. Generally, services are transmitted on theworking tunnel. When the working tunnel is faulty, APS occurs and the services are switchedto the protection tunnel.



43

Figure 4-22 Typical application of tunnel APS (for co-sourced tunnels with different sinks)

NodeB

PE1

PE3

PE2

MC-LAG

RNC

PSN

Tunnel APS A

S

Working Tunnel

Multi-chassis synchronous communication

Active (carrying services)

Standby (not carrying services)

Protection Tunnel

A

S

MRPSThis section defines MRPS and describes its purpose.

DefinitionAs shown in Figure 4-23 and Figure 4-24, MRPS protects packet services on ring topologiesby switching the services to the prepared protection channel when the working channel fails.



44

Figure 4-23 Application of MRPS scenario 1

RNC

NodeB

NE1

NE2NE3

NE4NE5

RNC

NodeB

NE1

NE2NE3

NE4NE5



45

Figure 4-24 Application of MRPS scenario 2

RNC

NodeB

NE1

NE2NE3 NE4

NE5NE6

NE7

RNC

NodeB

NE1

NE2NE3 NE4

NE5NE6

NE7

Purposes and Benefits

MRPS provides the following unique benefits:

l Saving tunnel resources.MRPS uses less tunnel resources because it only requires configuring working tunnels forservices.

l Saving equipment processing resources and bandwidth resources.MRPS requires that each node use two OAM instances and two ring APS instances.Quantities of OAM instances and APS instances are independent of service quantities.Therefore, MRPS consumes less equipment processing resources and bandwidth resources.

l Reducing configuration and maintenance workload.After a node is added to the protection channel of MRPS, you only need to configure thenew node.



46

l Enhancing protection reliability.

MRPS protects services against a link failure or several nodes failure.

ERPS

Ethernet technologies are applied more widely than ever before, and ring networking usingpacket Ethernet boards is more and more deployed. Under the context, Ethernet ring protectionswitching (ERPS) can be used to protect LAN services on packet Ethernet ring networks.

When an Ethernet ring network is configured with ERPS, under normal conditions, the ringprotection link (RPL) owner node blocks its port on a certain side so that services are transmittedthrough the port on the other side. In this manner, service loops are prevented. If a ring link ora ring node fails, the RPL owner unblocks the preceding port and then the services are transmittedthrough the unblocked port.

ERPS has the following characteristics in its implementation:

l Specifies an RPL and blocks its ports to prevent loops.

l Defines R-APS messages to transmit ring network status information so as to ensureconsistent protection operations performed on ring nodes.

Figure 4-25 shows networking of a single Ethernet ring protection (ERP) ring.

Figure 4-25 A single ERP ringNE 1

NE 2

NE 3

NE 4

1

2

3

4Topology

Protection switching

NE 1

NE 2

NE 3

NE 4

1

2

3

4Topology

Link down

RPL RPL

Blocked port

Ethernet service direction

RPL owner node

RPL neighbor node

RPL neighbor node

RPL owner node

As shown in Figure 4-25, NE4 is the RPL owner node and NE1 is a neighbor node. The linkbetween NE1 and NE4 is the RPL.

l Under normal conditions, NE4 blocks the port connected to NE1, and NE1 also blocks theport connected to NE4a. Services are transmitted along the route NE1 <-> NE2 <-> NE3<-> NE4.

l If the link between NE1 and NE2 fails, NE4 and NE1 unblock their ports so that servicescan be transmitted along the route NE1 <-> NE4 <-> NE3 <-> NE2.

NOTE

a: If ERPS V1 is used, NE1 does not block the port connected to NE4.

Figure 4-26 shows networking of tangent ERP rings.



47

Figure 4-26 Tangent ERP ringsNE 1

NE 2

NE 3

NE 4

1

2

3

4topology

NE 5

NE 6

NE 7

3

5

6

7topology


NE 1

NE 2

NE 3

NE 4

1

2

3

4topology

NE 5 NE 7

3

5

6

7topology

RPL

RPL

RPL

RPL

NE 6

ERP ring 1

ERP ring 2

ERP ring 1

ERP ring 2

Link down

Blocked port


RPL owner node

RPL neighbor node

RPL neighbor node

RPL neighbor node

RPL neighbor node

RPL owner node

RPL owner node

RPL owner node

As shown in Figure 4-26, ERP ring 1 is tangent to ERP ring 2 at NE3. On ERP ring 1. NE4 isthe RPL owner node and NE1 is a neighbor node. The link between NE1 and NE4 is the RPLlink. On ERP ring 2, NE6 is the RPL owner node and NE7 is a neighbor node. The link betweenNE6 and NE7 is the RPL.

l Under normal conditions:– On ERP ring 1, NE4 blocks the port connected to NE1, and NE1 also blocks the port

connected to NE4. Services are transmitted along the route NE1 <-> NE2 <-> NE3 <-> NE4.

– On ERP ring 2, NE6 blocks the port connected to NE7, and NE7 also blocks the portconnected to NE6. Services are transmitted along the route NE7 <-> NE3 <-> NE5 <-> NE6.

l If the link between NE1 and NE2 fails:– On ERP ring 1, NE4 and NE1 unblock their ports so that services can be transmitted

along the route NE1 <-> NE4 <-> NE3 <-> NE2.– On ERP ring 2, ports connecting NE6 and NE7 are still blocked, and services are

transmitted along the route NE7 <-> NE3 <-> NE5 <-> NE6.

Figure 4-27 shows networking of interconnected ERP rings.

Figure 4-27 Interconnected ERP ringsRPL

2

6 5

3

NE 1 NE 2

NE 3 NE 4

NE 5RPL

1

2 3

4

RPL

2

6 5

3

NE 1 NE 2

NE 3 NE 4

NE 5 NE 5RPL

1

2 3

4


Link down

Blocked port


RPL neighbor node

RPL owner node

RPL owner node

RPL neighbor node

topology

ERP ring 1

topology

ERP ring 2

RPL neighbor node

RPL owner node

RPL owner node

RPL neighbor node

topology

ERP ring 1

topology

ERP ring 2



48

As shown in Figure 4-27, ERP ring 1 and ERP ring 2 are interconnected at NE3 and NE4. OnERP ring 1, NE2 is the RPL owner node and NE1 is a neighbor node. The link between NE1and NE2 is the RPL. On ERP ring 2, NE5 is the RPL owner node and NE6 is a neighbor node.The link between NE5 and NE6 is the RPL.

l Under normal conditions: On ERP ring 1, NE2 blocks the port connected to NE1, and NE1also blocks the port connected to NE2. Services are transmitted along the route NE2 <->NE4 <-> NE3 <-> NE1. On ERP ring 2, NE5 blocks the port connected to NE6, and NE6also blocks the port connected to NE5. Services are transmitted along the route NE1 <->NE3 <-> NE4 <-> NE2.

l If the link between NE1 and NE3 fails: On ERP ring 1, NE1 and NE2 unblock their portsso that services can be transmitted along the route NE1 <-> NE2 <-> NE4 <-> NE3. OnERP ring 2, ports connecting NE5 and NE6 are still blocked, and services are transmittedalong the route NE3 <-> NE5 <-> NE6 <-> NE4.

LAG

As the Ethernet technology is widely applied in the metropolitan area network (MAN) and thewide area network (WAN), carriers propose increasingly higher requirements on the bandwidthand reliability of access links that use the Ethernet technology. Hardware upgrades can increaseEthernet link bandwidth but also incur high expenditure. In addition, hardware upgrades are lessflexible than software upgrades. To increase bandwidth at a low expenditure and flexibly, thelink aggregation technology is developed.

Link aggregation has the following characteristics:

l With no need for hardware upgrades, link aggregation binds several Ethernet ports as ahigher-bandwidth logical port.

l The link backup mechanism of the link aggregation technology provides higher linktransmission reliability.

l Link aggregation functions between adjacent NEs and is independent of the networktopology.

The logical link aggregating several physical links is called a link aggregation group (LAG).

NOTE

Link aggregation is also called port aggregation because each link corresponds to two specific ports at twoends in Ethernet transmission.

As shown in Figure 4-28, two adjacent NEs are interconnected through three pairs of Ethernetports. Three physical Ethernet links are bound as a logical link, called a LAG.

Figure 4-28 LAG

Ethernet packet

Link 1

LAG

Link 2

Link 3 Ethernet packet



49

LPTThis section defines LPT and provides the purpose of this feature.

DefinitionLink-state pass through (LPT) detects a fault that occurs at a service access node or on a servicenetwork and then instructs the equipment at both ends of the network to switch to a backupnetwork. LPT ensures normal data transmission. As shown in Figure 4-29, LPT-enabled NE1and NE2 will disconnect their access links from router A and router B if access link 1, accesslink 2, or the service network becomes faulty. When router A and router B detect a link faultbetween them, they immediately switch to the backup network.

Figure 4-29 Typical application of LPT

NE1 NE2Access link 1 Access link 2Router A Router B

Service network

Backup network

Working link

Protection link

PurposeLPT enabled access equipment detects link faults and immediately switches to a backup network.

MSTPThis topic defines MSTP and describes the purpose of this feature.

DefinitionThe spanning tree protocol (STP) is used in network loops. This protocol uses algorithms tobreak a loop network into a loop-free tree network to prevent packets from cycling endlessly inthe loop network. See Figure 4-30.



50

Figure 4-30 Diagram of the STPSwitch A

Root: Switch A

Switch B Switch C

Switch A

Switch B Switch C

The rapid spanning tree protocol (RSTP) is an optimized version of STP. RSTP stabilizesnetwork topology more quickly than STP. RSTP is compatible with STP. STP packets and RSTPpackets can be differentiated by the bridge that uses the RSTP for calculating the spanning tree.

Compared with STP and RSTP, MSTP maximizes link bandwidth usage by setting up severalindependent spanning trees.

Purpose

STP/RSTP meets the following requirements:

l Any activated bridge topology can be configured as a single spanning tree. Redundant dataloops between two stations in a network topology should be removed.

l The spanning tree topology can be configured to protect against bridge faults or routeinterruptions. Temporary data loops can be prevented by automatically accepting thebridges and bridge ports of the bridges that are newly added into the LAN.

l A topology that has been activated can be predicted and repeated. In addition, the topologycan be selected by managing algorithm parameters.

l Operations to the end stations are transparent. For example, the end stations do not knowwhether they are attached to a single LAN or a bridged LAN.

l A small part of the available link bandwidth is used to create and maintain a spanning tree.Bandwidth does not increase with the expanding network scale.

STP/RSTP have shortcomings that have become apparent as VLAN technology has developed.After the STP/RSTP is enabled, a loop network is broken into a single spanning tree and theblocked links do not carry any traffic. This wastes bandwidth.

MSTP has fixed this defect in STP and RSTP in addition to stabilizing the network topology.MSTP provides a load sharing mechanism that enables the traffic of different VLANs to betransmitted over their respective trails.

l MSTP divides a switching network into different regions, called MST regions. Multiplespanning trees that are independent of each other exist in each region. Each spanning treeis called a multiple spanning tree instance (MSTI).

l When MSTP is enabled, VLAN mapping tables specify the mapping relationships betweenVLANs and MSTIs. Each VLAN in an MST region corresponds to one MSTI and only this



51

MSTI can transmit data for this VLAN. One MSTI, however, may be mapped to multipleVLANs.

Consider the network in Figure 4-31 as an example. VLAN 1 and VLAN 2 packets aretransmitted over the network. When STP/RSTP is enabled, a single spanning tree that uses switchA as the root switch is generated and the links between switch B and switch C are blocked.Hence, the bandwidth of this link is not utilized.

Figure 4-31 Limitations of the STP/RSTP

Switch A

Switch B Switch C

Spanning tree

Root switch

Host A

Host B Host C

Blocked port

VLAN 1VLAN 2

If MSTP is enabled and this network is an MST region, then VLAN 1 and VLAN 2 are eachmapped to an MSTI. Figure 4-32 shows the network topology. On the ring:

l MSTI 1 uses switch A as the root switch to forward packets of VLAN 1.l MSTI 2 uses switch C as the root switch to forward packets of VLAN 2.

Different VLANs are forwarded over different trails and all VLAN packets are forwardedcorrectly. Load sharing is achieved.



52

Figure 4-32 MSTP improvement

MSTI 2 -> VLAN 2

Switch A

Switch B Switch C

VLAN 1VLAN 2

Host A

Host B Host C

Switch A

Switch B Switch C

VLAN 1 VLAN 1

Switch A

Switch B Switch C

VLAN 2

MSTI 1 -> VLAN 1

VLAN 2

Root switch

NOTE

The OptiX OSN 500 supports only the MSTP that generates a common and internal spanning tree (CIST). TheOptiX OSN 500 does not support the load sharing function that is forwards packets of different VLANs overdifferent trails.

As shown in Figure 4-33, when equipment uses two different trails to access the OptiX OSNequipment, you can configure the OptiX OSN equipment ports connected to the user networkinto a port group. This port group, together with a switch on the user network, can run the MSTP.If a service access link becomes faulty, MSTP generates a spanning tree topology to provideprotection for a user network that is configured with multiple access points.



53

Figure 4-33 Typical MSTP scenario on the OptiX OSN equipment

CIST

Root Root

Port group

Blocked Port

ML-PPP

This section defines ML-PPP and describes the purpose of using this feature on transportnetworks.

Definition

The Point-to-Point Protocol (PPP) is a link layer protocol based on the Serial Line InterfaceProtocol (SLIP). PPP provides a standard method for encapsulating multiple types of protocoldatagrams (including IP, IPX, and AppleTalk) on a point-to-point link.

The Multilink Point-to-Point Protocol (ML-PPP) is an extended PPP protocol. It is used to bindmultiple low-rate PPP links into a virtual ML-PPP link. An ML-PPP link is also called a MultilinkProtocol (MP) group. ML-PPP also supports packet splitting and recombination, thereforeeffectively reducing the transmission latency and increasing the maximum transfer unit (MTU)for a link.

Using the ML-PPP function brings a network the following benefits:

l Increased bandwidth

l Load sharing and link backup

l Lower latency

Purpose

ML-PPP links can bear MPLS tunnels so that the MPLS tunnels can traverse a TDM transportnetwork.

As shown in Figure 4-34, MPLS packets in the MPLS tunnel are encapsulated in E1s andtransmitted over the ML-PPP link through the TDM network. At the TDM network edge, theMPLS packets are decapsulated from E1s.



54

Figure 4-34 Using an ML-PPP link to transmit services through a TDM network

Ingress


FE/GE E1 E1TDM

network

Transit Transit Egress

MPLS tunnel

Payload PayloadMPLSMPLS

ML-PPPFE/GE

E1

FE/GE

PayloadMPLS

FE/GE

Linear MSPThe packet-based linear MSP uses the MSOH bytes K1 and K2 to implement automaticprotection switching and thus to protect services. The OptiX OSN equipment supports 1:1packet-based linear MSP.

1:1 Packet-based linear MSP1:1 packet-based linear MSP requires one working path and one protection path. Commonservices are transmitted in the working path. When the working path becomes faulty, the servicein this path is switched to the protection path. Figure 4-35 shows the application of 1:1 packet-based linear MSP.

NOTE

The extra traffic can not be transmitted in the protection path.



55

Figure 4-35 1:1 Packet-based linear MSP

Working path

Protection path

NE A NE B


NE A NE B

Common service

Working path

Protection path

Common service

Common service

Common service

PurposeThe packet-based linear MSP scheme uses the MSOH bytes K1 and K2 to implement automaticprotection switching once the working path fails, and thus to protect services.

4.2.3 Network Level Protection (TDM)This section describes protection schemes in the TDM domain.

LAGLink aggregation combines multiple links attached to the same equipment into a LAG so thatthe bandwidth of the LAG increases and links are made more reliable. The aggregated links aretreated as a single logical link.

A LAG aggregates multiple physical links to form a logical link that transmits data at a higherrate. Link aggregation functions between adjacent equipment. It does not have any impact onthe architecture of the entire network. Link aggregation is also called port aggregation becauselinks have a one-to-one mapping with ports on Ethernet networks.

As shown in Figure 4-36, the LAG provides the following functions:l Increased bandwidth

LAGs provide users with a cost-effective method for increasing link bandwidth. Bycombining multiple physical links into one logical link, users obtain a logical link withhigher bandwidth without upgrading existing equipment, since the bandwidth of the logical



56

link is equal to the sum of the bandwidth of all combined physical links. The aggregationmodule uses a load sharing algorithm to share traffic among the combined links.

l Increased availabilityThe links in a LAG dynamically back up each other. When a link fails, the other links inthe LAG take over. Dynamic backup occurs only among links in the LAG; other links arenot included.

Figure 4-36 Link aggregation group

LAG

Ethernetpackets

Link 1

Link 2

Link 3 Ethernetpackets

DLAGThe DLAG is a protection group that aggregates two corresponding ports on two identical boards.The DLAG provides 1+1 protection for the inter-board ports.

As shown in Figure 4-37, a DLAG uses two identical boards. One board functions as the mainboard, and the other board functions as the slave board. Two corresponding ports, one port onthe main board and the other port on the slave board, form a DLAG. For example, PORT1 onthe main board and PORT1 on the slave board form the first DLAG. By default, the port on themain board is in the working state, and the port on the slave board protects the port on the mainboard.



57

Figure 4-37 DLAG

Main board

Main communication equipment

Slave communication equipment

Main link 1

A

B

C

XCS

Slave board

PORT1PORT2PORT3PORT4

PORT1

PORT2PORT3PORT4

VCG

VCG

Main link 2

Main link 3

Slave link 1

Slave link 2

Slave link 3



B



After the DLAG is configured, when the main board detects a link down failure, a board offlineevent, or a hardware failure on a port, the cross-connect board switches the services carried bythe failed port from the main board to the slave board to protect the services.

The DLAG provides the following functions:

l Increased link availability

The main port and slave port in a DLAG provide backup to each other dynamically. Whenthe main link fails, the slave link quickly replaces the failed main link, thus increasing theavailability of the links.

l Reduced the impact of protection switching

When the link on a port fails, only the services on the port are switched to the correspondingport on the slave board. The services on the other ports that work normally are not switched.For example, when main link 1 fails, only the services carried by main link 1 are switchedto slave link 1 that is between PORT1 on the slave board and the slave communicationequipment at the opposite end.

l Improved security and convenience in the case of a network upgrade

When you upgrade an NE, you can first upgrade the slave board, then switch the servicesfrom the main board to the slave board, and finally upgrade the main board. In this way,the services are upgraded without being interrupted.

LCAS

This topic describes the LCAS in terms of background, function definition, and benefits tonetworks.



58

With the diverse and complex development of the services transmitted in the SDH network, thedemands for various access bandwidths increasingly grow. As a result, the previous monotonebandwidth (such as a VC-4) no longer meets the requirement. Hence, the concatenationtechnology emerges as the times require. Concatenation is classified into adjacent concatenationand virtual concatenation. The latter is more flexible than the former and enjoys higherbandwidth utilization than the former does. Both the adjacent concatenation and virtualconcatenation have the following problems:

l When any physical channel fails, all the concatenated channels fail and all services areinterrupted.

l After services are set up, if you adjust the bandwidth of the services, the services are greatlyaffected.

The link capacity adjustment scheme (LCAS) technology emerges as a solution to the precedingproblems. The LCAS improves and complements the virtual concatenation technology. TheLCAS dynamically adjusts the number of virtual containers required for service mapping tomeet the requirements of various service bandwidths. This elevates the bandwidth utilizationand enhances the robustness of virtual concatenation.

NOTE

The LCAS applies to only the virtually concatenated channels.

Adopting the LCAS function brings the network with the following benefits:

l The LCAS dynamically adjusts (adds or deletes) the service bandwidth without affectingthe availability of the existing services.

l When some of the physical channels in a virtual concatenation group fail, with LCAS, thefailed channels are shielded and the other physical channels still transport the servicesnormally. This prevents the services from being interrupted when some of the physicalchannels fail. After the failed physical channels are restored, they can transport services.

LPTThis section defines LPT and provides the purpose of this feature.

DefinitionLink-state pass through (LPT) detects a fault that occurs at a service access node or on a servicenetwork and then instructs the equipment at both ends of the network to switch to a backupnetwork. LPT ensures normal data transmission. As shown in Figure 4-38, LPT-enabled NE1and NE2 will disconnect their access links from router A and router B if access link 1, accesslink 2, or the service network becomes faulty. When router A and router B detect a link faultbetween them, they immediately switch to the backup network.



59

Figure 4-38 Typical application of LPT

NE1 NE2Access link 1 Access link 2Router A Router B

Service network

Backup network

Working link

Protection link

PurposeLPT enabled access equipment detects link faults and immediately switches to a backup network.

Ring MSPRing MSP uses the multiplex section overhead (MSOH) bytes K1 and K2 to implementautomatic protection switching of services.

Two-Fiber Unidirectional Ring MSPOn a two-fiber unidirectional ring MSP, one of the bidirectional STM-N lines is the workingline, and the other is the protection line. As shown in Figure 4-39, the services on the two-fiberunidirectional ring MSP are on diverse routes. Before the protection switching, the signal flowof the services from NE A to NE C is NE A→NE B→NE C, and the signal flow of the servicesfrom NE C to NE A is NE C→NE D→NE A.

In normal cases, services are transmitted on the working line. When a fiber cut occurs and theworking line becomes unavailable, the services on the two ends of the faulty point are bothswitched from the working line of the faulty fiber to the protection line of the reverse directionalfiber for transmission. Figure 4-39 shows the application of the two-fiber unidirectional ringMSP. After the protection switching, the signal flow of the services from NE A to NE C is NEA→NE D→NE C→NE B→NE C, and the signal flow of the services from NE C to NE Acontinues to be NE C→NE D→NE A.



60

Figure 4-39 Two-fiber unidirectional ring MSP

Signal flow of services

NE A

NE B

NE C

NE D

East


West

West

East

East

East

West

West

Two-fiber unidirectional MSP

ring

Before protection switching

NE A

NE B

NE C

NE D

East West

West

East

East

East

West

West

Two-fiber unidirectional MSP

ring

After protection switching

Two-Fiber Bidirectional Ring MSP

On a two-fiber bidirectional ring MSP, the first half of VC-4s on each STM-N line is allocatedto the working channel, and the other half of VC-4s is allocated to the protection channel. Asshown in Figure 4-40, the services on the two-fiber bidirectional ring MSP are on uniform routes.Before the protection switching, the signal flow of the services from NE A to NE C is NE A→

NE B→NE C, and the signal flow of the services from NE C to NE A is NE C→NE B→NE A.

In normal cases, services are transmitted on the working channel. The services transmitted ontwo fibers flow in inverse directions. When a fiber cut occurs and the working channel becomes



61

unavailable, the services on the two ends of the faulty point are both switched from the workingchannel of the faulty fiber to the protection channel of the reverse directional fiber fortransmission. Figure 4-40 shows the application of the two-fiber bidirectional ring MSP. Afterthe protection switching, the signal flow of the services from NE A to NE C is NE A→NE D→

NE C→NE B→NE C, and the signal flow of the services from NE C to NE A is NE C→NEB→NE C→NE D→NE A.

Figure 4-40 Two-fiber bidirectional ring MSP

Signal flow of services

NE A

NE B

NE C

NE D

East


West

West

East

East

East

West

West

Two-fiber bidirectional MSP

ring

Before protection switching

NE A

NE B

NE C

NE D

East West

West

East

East

East

West

West

Two-fiber bidirectional MSP

ring

After protection switching

Linear MSPThe linear MSP uses the K1 and K2 bytes in the multiplex section overhead to realize automaticprotection switching. The OptiX OSN equipment supports 1+1 and 1:N linear MSP.

1+1 Linear MSPThe 1+1 linear MSP requires one working channel and one protection channel. At the sourcenode, the service is dually fed to the working channel and protection channel. At the sink node,



62

the service is received from the working channel. When the working channel becomes faulty,the service is received from the protection channel. Figure 4-41 shows the application of the 1+1 linear MSP.

Figure 4-41 1+1 linear MSP

Working channel

Protection channel

NE A NE B


Working channel

Protection channel

NE A NE B

NOTE

No extra traffic can be configured in the protection channel in a 1+1 linear MSP group.

1:N linear MSPThe 1:N linear MSP requires N working channels and one protection channel. Common servicesare transmitted on the working channels, and extra traffic is transmitted on the protectionchannel. When a working channel becomes faulty, the service on the channel is switched to theprotection channel. Therefore, the extra traffic is interrupted. Figure 4-42 shows the applicationof the 1:N linear MSP.



63

Figure 4-42 1:N linear MSP

Workingchannel 1

Protectionchannel

NE A NE B


... ...

NE A NE B

... ...Workingchannel N

Workingchannel N

Workingchannel 1

Protectionchannel

Extra traffic

Common service 1

Common service N

Extra traffic

Common service 1

Common service N

Extra traffic

Common service 1

Common service N

Extra traffic

Common service 1

Common service N

PurposeThe LMSP scheme uses the MSOH bytes K1 and K2 to implement automatic protectionswitching once the working path fails, and therefore to protect services.

SNCPSNCP requires one working subnet and one protection subnet so that services can be dually-fedand selectively-received.

SNCP requires one working subnet and one protection subnet so that services can be dually-fedand selectively-received. If the working subnet fails to be connected or if its performance failsto meet requirements, the protection subnet takes over.

Figure 4-43 shows the application of SNCP.



64

Figure 4-43 Application of SNCP

WorkingSNC

ProtectionSNC

Source end

NE A NE B

Sink end

NE A NE B

Protectionswitching

Source end Sink end

WorkingSNC

ProtectionSNC

4.3 SynchronizationThe OptiX OSN 550 supports IEEE 1588v2, synchronous Ethernet clock, 2 MHz, and 2 Mbit/s clocks and can provide an end-to-end clock transport solution when deployed with MSTP orPTN products.

When the OptiX OSN 550 uses IEEE 1588v2 to implement phase synchronization, it supportsthe following NE clock types: OC, TC, BC and TC+BC.

4.3.1 Requirements for Clock SynchronizationThis section describes frequency and phase synchronization requirements of service networks.

A service network, especially a radio access network (RAN), has stringent requirements forclock synchronization, and clock signals transmitted over a transport network must meet theserequirements.

Clock synchronization requirements of mobile communication networks

Table 4-4 lists clock synchronization requirements of mobile communication networks basedon the wireless access mode.



65

Table 4-4 Clock synchronization requirements of mobile communication networks

Wireless Access Mode Precision of FrequencySynchronization

Precision of PhaseSynchronization

GSM 0.05 ppm Phase synchronization isnot required.

WCDMA 0.05 ppm Phase synchronization isnot required.

TD-SCDMA 0.05 ppm ±1.5 us

CDMA2000 0.05 ppm ±3 us

WiMax FDD 0.05 ppm Phase synchronization isnot required.

WiMax TDD 0.011 ppm/3.5G, 7 carrierwave

±1 us

LTE FDD 0.05 ppm Phase synchronization isnot required.

LTE TDD 0.05 ppm ±1.5 us

Phase synchronization requirements of other common systemsBilling and network management systems also require phase synchronization. Table 4-5 liststhe phase synchronization requirements of some common systems.

Table 4-5 Phase synchronization requirements of other common systems

System Phase Synchronization Precision

Billing system 500 ms

Communication network managementsystem

500 ms

Signaling system No. 7 1 ms

Positioning system 1 us (equivalent to a positioning precision of300 m)

4.3.2 Clock and Time SynchronizationThis section describes synchronization features including clock synchronization andsynchronous Ethernet clock.



66

SDH Synchronization ClocksClock synchronization on the entire network helps to transmit services normally.

DefinitionClock: The electronic circuit in a computer that generates a steady stream of timing pulses.

PurposeClock synchronization ensures that all the digital devices on a communications network workat the same nominal frequency, and therefore minimizes the impacts of slips, burst bit errors,phase jumps, jitters, and wanders on digital communications systems. Clock synchronizationalso minimizes pointer justifications on SDH devices. Therefore, clock synchronization is theprecondition and basis for the normal operation of a network.

When all the NEs on the entire network trace clock signals from the same clock source, thenetworkwide synchronization is realized.

Generally, an NE can obtain the PRC through several paths. In Figure 4-44, NE4 can trace theclock from NE3 or the clock from NE5. These two clock sources are from the same PRC.

Figure 4-44 Clock synchronization

NE1

NE6

NE5

NE4

NE3

NE2

BITS

Clock signal flow



67

Synchronous Ethernet ClockThe synchronous Ethernet clock is a technology that extracts clock signals from serial bit streamson an Ethernet line, and transmits the extracted clock signals with services to implement thetransfer of the clock signals.

DefinitionThe synchronous Ethernet clock is a technology of frequency synchronization over the physicallayer. The system directly extracts the clock signal from the serial bit stream on the Ethernetline, and transmits the data to each board by using the clock signal to realize the transfer of clockinformation.

PurposeAs SDH networks are evolving into data networks, carrier-level large-scale networks requiresynchronous Ethernet to transmit clock signals. The networkwide synchronous transmission ideaof the SDH system needs to be introduced to the Ethernet design. Clock signals are transmittedfrom the core to the edge by using the Ethernet physical layer, which ensures synchronizationfor all types of real-time services.

In a TDM network or packet network, Figure 4-45 shows the typical network to whichsynchronous Ethernet is applied networkwide. BITS1 and BITS2 respectively transmit clocksignals to NE1 and NE2 through external clock ports. NE1 and NE2 transmit the clock signalsto NE3. NE3 transmits the clock signals from the convergence layer to access-layer NEs. Theaccess-layer NEs transmit the clock signals to NodeBs. In this manner, networkwide clocksynchronization is achieved.



68

Figure 4-45 Typical network to which synchronous Ethernet is applied networkwide

2.5 Gbit/s chain

Access layer

Convergence layer

622 Mbit/s chain

GE ring

Clock information

OptiX OSN access equipment

OptiX OSN convergence equipment

Clock information

Node B Node B Node B

BITS1 BITS2

NE1 NE2

NE3 NE4

NE5 NE6 NE7

Clock information

155 Mbit/s chain

In a packet network, Figure 4-46 shows a typical network that uses both synchronous Ethernetand IEEE 1588 ACR. BITS1 and BITS2 respectively transmit clock signals to Router1 andRouter2 through external clock ports. Because Router1 and Router2 need to transmit the clocksignals to convergence-layer NEs (NE1 and NE2) through a non-transport network, they convertthe clock signals into IEEE 1588 ACR clock signals. After the IEEE 1588 ACR clock signalstraverse the non-transport network and reach NE1 and NE2, the two NEs restore the signals intosynchronous Ethernet clock signals and transmit them to NE3. NE3 transmits the clock signalsto access-layer NEs. The access-layer NEs transmit the clock signals to NodeBs. In this manner,networkwide clock synchronization is achieved.

NOTE

Currently, the equipment supports only the conversion of IEEE 1588 ACR clock signals into synchronousEthernet signals.



69

Figure 4-46 Typical network that uses both synchronous Ethernet and IEEE 1588 ACR

Access layer

Convergence layer



Clock information

Clock information

Synchronous ethernet clock


BITS1 BITS2

NE1 NE2

NE3 NE4

NE5 NE6 NE7

IEEE 1588 ACR




Clock information

Router1 Router2



70

IEEE 1588v2This section provides the definition of IEEE 1588v2 and describes its purpose.

DefinitionThe IEEE 1588v2 defines a Precision Clock Synchronization Protocol for NetworkedMeasurement and Control Systems. It defines the Precision Time Protocol (PTP) to synchronizeindependent clocks running on separate nodes of a distributed measurement and control systemto a high degree of accuracy and precision. The IEEE 1588v2 standard supports timesynchronization accuracy in the submicrosecond range.

Synchronization involves clock synchronization (also called frequency synchronization) or timesynchronization. The IEEE 1588v2 standard mainly applicable to time synchronization, and itcan also be used for clock synchronization.

l Clock synchronizationTo achieve synchronization of clocks for two devices, the pulses of the clocks must be atthe same frequency and keep a constant phase difference.

l Time synchronizationTo achieve time synchronization, the pulses of the clocks must be at the same frequencyand have a very small phase difference as required, and the times indicated by the clocksmust be measured in the same timescale. The commonly used timescales include universalcoordinated time (UTC) and international atomic time (TAI, from the French name TempsAtomique International).

PurposeIn the applications on transmission networks, the IEEE 1588v2 standard provides an approachto 1588v2 time synchronization on a network basis, with a synchronization accuracy in themicrosecond range; as well, the IEEE 1588v2 standard helps in transparent transmission of1588v2 time signals. As such, the IEEE 1588v2 standard, as an alternative to the globalpositioning system (GPS) or other complex timing systems, can be used to provide 1588v2 timefor NodeBs or eNodeBs. Figure 4-47 illustrates an application example wherein the IEEE1588v2 standard helps to synchronize the time of NodeBs distributed in a CDMA2000 or TD-SCDMA communication system.



71

Figure 4-47 Time synchronization of NodeBs implemented by the IEEE 1588v2 standard

RNC

TimesynchronizationPTP node

NodeB NodeB NodeB

BITS

IEEE 1588 ACRThis section defines IEEE 1588 ACR and describes the purpose of using this feature.

DefinitionIEEE 1588 adaptive clock recovery (ACR) is a technology used to achieve frequencysynchronization between the clock equipment that supports the IEEE 1588v2 standard. To bespecific, the master equipment encapsulates the local system clock into a Sync packet as atimestamp and transmits the Sync packet to a packet switched network (PSN), which forwardsthe Sync packet to the slave equipment. On receiving the Sync packet, the slave equipmentextracts the timestamp from the Sync packet and recovers the clock frequency by using the ACRalgorithm. In this way, the clock frequency of the PTP equipment at the two ends of a PSN issynchronized.

IEEE 1588 ACR achieves only frequency synchronization but not time synchronization.

PurposeWith the IEEE 1588 ACR technology applied on a transport network, the clock frequency iscarried in an IEEE 1588v2 packet, which traverses an asynchronous PSN. As a result, the clockfrequency of the equipment at the two ends of the PSN is synchronized.

In the network as shown in Figure 4-48, the PTP node on the RNC side encapsulates the clockfrequency of the building integrated timing supply (BITS) equipment into an IEEE 1588v2



72

packet, which traverses the asynchronous PSN. On receiving the IEEE 1588v2 packet, the PTPnodes on the NodeB side recover the clock frequency of the BITS equipment from the IEEE1588v2 packet by using the ACR algorithm, and send the clock frequency to the NodeBs. In thisway, the clock frequencies of the NodeBs are synchronized with the clock frequency of the RNC.

Figure 4-48 IEEE 1588 ACR frequency synchronization

NodeB

NodeB

NodeB

RNC

BITS

PTP node

Transparenttransmission of

frequency

Frequencysynchronization

Router/Switch

PSN

Equipment on a transport network supports the conversion of IEEE 1588 ACR clock signalsfrom a non-transport network into synchronous Ethernet clock signals to achieve networkwidefrequency synchronization.

As shown in Figure 4-49, BITS1 and BITS2 respectively transmit clock signals to Router1 andRouter 2 through external clock ports. Because Router1 and Router2 need to transmit the clocksignals to convergence-layer NEs (NE1 and NE2) through a non-transport network, they convertthe clock signals into IEEE 1588 ACR clock signals. After the IEEE 1588 ACR clock signalstraverse the non-transport network and reach NE1 and NE2, the two NEs restore the signals intosynchronous Ethernet clock signals and transmit them to NE3. NE3 transmits the clock signalsto access-layer NEs. The access-layer NEs transmit the clock signals to NodeBs. In this manner,networkwide frequency synchronization is achieved.

NOTE

Currently, the equipment supports only the conversion of IEEE 1588 ACR clock signals into synchronousEthernet signals.



73

Figure 4-49 Typical network that uses both synchronous Ethernet and IEEE 1588 ACR

Access layer

Convergence layer



Clock information

Clock information



BITS1 BITS2

NE1 NE2

NE3 NE4

NE5 NE6 NE7

IEEE 1588 ACR




Clock information

Router1 Router2



74

CES ACRThis section defines CES ACR and describes the purpose of using this feature.

DefinitionCES ACR uses the adaptive clock recovery (ACR) technology to recover clock synchronizationinformation carried by CES packets. CES ACR is available in two types: standard and enhanced.

In a standard CES ACR solution, the source end (Master) uses the local clock information asthe timestamp in a Real-time Transport Protocol (RTP) packet header and encapsulates the localclock information in a CES packet. The sink end (Slave) recovers the clock using the timestampin the packet. This method prevents signal impairment during the transmission.

The OptiX OSN equipment adopts the enhanced timestamp clock solution. That is, clocks canbe recovered based on SN in CES packets rather than timestamps in RTP packet headers. SeeFigure 4-50.

Figure 4-50 CES ACR clock solution

PSN

PE1 PE2BTS BSC


CES

Primaryreference

clock

E1

E1CES

Master

SN

ProcessingProcessing

SN

CESE1

Slave

E1

SN: Sequnce Number

PurposeIn the packet domain, CES ACR is mainly used to transparently transmit E1 clocks in the PSN.



75

5 Hardware and Structure

About This Chapter

This section describes the chassis, boards, and external components of the equipment.

5.1 ChassisThis section describes the structure, slot layout, and access capacity of the chassis.

5.2 Outdoor CabinetThe equipment operating in a high-temperature and dust-concentrated outdoor environmentneeds to be installed in an outdoor cabinet.

5.3 Board CategoryThis section describes the boards that the equipment supports. Different boards provide theequipment with different functions.

OptiX OSN 550 Multi-Service CPE Optical TransmissionSystemProduct Description 5 Hardware and Structure


76

5.1 ChassisThis section describes the structure, slot layout, and access capacity of the chassis.

5.1.1 Chassis StructureThis section describes the chassis structure and equipment labels.

Chassis Structure and Board Installation Area

Board installation

area

SLOT9

(PIU)

SLOT 7 (CST/CSH)

SLOT 1 (EXT )

SLOT 5 (EXT)

SLOT 3 (EXT)

SLOT 2 (EXT )

SLOT 4 (EXT)

SLOT 6 (EXT)

SLOT 8 (CST/CSH)SLOT10

(PIU) SLOT11

(FAN)SLOT92

(PIU)

SLOT 7

SLOT 1 (EXT)

SLOT 5 (EXT)

SLOT 3 (EXT)

SLOT 2 (EXT)

SLOT 4 (EXT)

SLOT 6 (EXT)

SLOT 8SLOT91

(PIU)SLOT

93(FAN)

Power supply boardsSystem control, switching, and timing boards

Extended boards

Fan board

1

2

34

1

2

3

4

W

H

D

NOTE

An OptiX OSN 550 NE can automatically save its NE ID, extended ID, IP address, and subnet mask to itsbackplane. After a new system control, switching, and timing board replaces an original one, the NEautomatically uses the saved information. Therefore, you do not need to set the NE ID, extended ID, IPaddress, and subnet mask for the substitute board.



77

Ventilation DesignThe chassis is densely covered with small air holes. Through these holes, air is let in from theleft and out from the right by fans.

NOTE

Ensure the smooth flow of air inside and around the equipment. Do not block the air intake vents and airexhaust vents of subracks when cabling. Keep the top of subracks clean.

Figure 5-1 Ventilation design of the OptiX OSN 550

AIR IN

AIR OUT

Label DescriptionTable 5-1 provides the description of the labels on the chassis and boards. Actual labels mayvary depending on the configurations of the chassis and boards.

Table 5-1 Description of labels

Label Label Name Description

ESD protection label Indicates that theequipment issensitive to staticelectricity.

Grounding label Indicates thegrounding positionof the chassis.

Fan warning label Warns you not totouch fan leaveswhen the fan isrotating.



78


Power caution label Instructs you toread relatedinstructions beforeperforming anypower-relatedtasks.

CLASS1LASER

PRODUCT

Laser safety classlabel

The laser safetyclass label CLASS1 indicates that themaximum opticalpower of theoptical port is lessthan 10 dBm (10mW).

合格证/ QUALIFICATION CARD

华为技术有限公司中国制造MADE IN CHINAHUAWEI TECHNOLOGIES CO.,LTD.

HUAWEI

Qualification cardlabel

Indicates that theequipment hasbeen qualitychecked.

RoHS label Indicates that theequipmentcontains certainhazardoussubstancesspecified in theRoHS directive.The equipmentneeds to berecycled after theenvironment-friendly use periodof 50 years expires.



79


l DC power

l AC power

Product nameplatelabel

Indicates theproduct name andcertification.

5.1.2 Cross-Connect and Slot Access Capacity (Packet)This section provides switching capacities and slot access capacities of the OptiX OSN 550 inpacket mode.

Switching CapacitiesTable 5-2 lists packet switching capacities when different system control, switching, and timingboards are installed.

Table 5-2 Switching capacities of the OptiX OSN 550

Board Maximum Switching Capacity (Gbit/s)

PCXLX 60

PCXX 60

PCXLG 40

PCXGA 20

PCXGB 40

Access Capacities of SlotsFigure 5-2 provides access capacities of slots when PCXLX/PCXX boards are installed on theOptiX OSN 550.



80

Figure 5-2 Access capacities of slots when PCXLX/PCXX boards are installed on the OptiXOSN 550

SLOT

9

(PIU)

SLOT 7 (CST/CSH)

SLOT 1 (EXT )

SLOT 5 (EXT)

SLOT 3 (EXT)

SLOT 2 (EXT )

SLOT 4 (EXT)

SLOT 6 (EXT)

SLOT 8 (CST/CSH)SLO

T10

(PIU)

SLOT11

(FAN)SLOT

92

(PIU)

SLOT 7

10Gbit/s

SLOT 5

SLOT 3

SLOT 2

SLOT 4

SLOT 6

SLOT 8 SLOT

91

(PIU)SLOT

93

(FAN)

SLOT 1 10Gbit/s

4Gbit/s 4Gbit/s

4Gbit/s 4Gbit/s

10Gbit/s 10Gbit/s

Figure 5-3 provides access capacities of slots when PCXGB/PCXLG boards are installed onthe OptiX OSN 550.

Figure 5-3 Access capacities of slots when PCXLG/PCXGB boards are installed on the OptiXOSN 550

SLOT

9

(PIU)

SLOT 7 (CST/CSH)

SLOT 1 (EXT )

SLOT 5 (EXT)

SLOT 3 (EXT)

SLOT 2 (EXT )

SLOT 4 (EXT)

SLOT 6 (EXT)

SLOT 8 (CST/CSH)SLO

T10

(PIU)

SLOT11

(FAN)SLOT

92

(PIU)

SLOT 7

10Gbit/s

SLOT 5

SLOT 3

SLOT 2

SLOT 4

SLOT 6

SLOT 8 SLOT

91

(PIU)SLOT

93

(FAN)

SLOT 1 10Gbit/s

4Gbit/s 4Gbit/s

4Gbit/s 4Gbit/s

1Gbit/s 1Gbit/s

Figure 5-4 provides access capacities of slots when PCXGA boards are installed on the OptiXOSN 550.

Figure 5-4 Access capacities of slots when PCXGA boards are installed on the OptiX OSN 550

SLOT

9

(PIU)

SLOT 7 (CST/CSH)

SLOT 1 (EXT )

SLOT 5 (EXT)

SLOT 3 (EXT)

SLOT 2 (EXT )

SLOT 4 (EXT)

SLOT 6 (EXT)

SLOT 8 (CST/CSH)SLO

T10

(PIU)

SLOT11

(FAN)SLOT

92

(PIU)

SLOT 7

2.5Gbit/s

SLOT 5

SLOT 3

SLOT 2

SLOT 4

SLOT 6

SLOT 8 SLOT

91

(PIU)SLOT

93

(FAN)

SLOT 1 2.5Gbit/s

4Gbit/s 4Gbit/s

4Gbit/s 4Gbit/s

1Gbit/s 1Gbit/s

5.1.3 Cross-Connect and Slot Access Capacity (TDM)This section provides cross-connect capacities and slot access capacities of the OptiX OSN 550in TDM mode.



81

Cross-Connect Capacities

Table 5-3 lists cross-connect capacities when different system control, switching, and timingboards are installed.

Table 5-3 Cross-connect capacities of the OptiX OSN 550

Board Higher Order Cross-Connect Capacity (Gbit/s)

Lower Order Cross-Connect Capacity (Gbit/s)

PCXLX/PCXX/PCXLG/PCXGA/PCXGB/CXL

20 5

Access Capacities of Slots

Access capacities of all slots are shown in Figure 5-5. The access capacity of a slot remains thesame regardless of whether the CXL, PCXLX, PCXX, PCXLG, PCXGA, or PCXGB board isinstalled.

Figure 5-5 Access capacities of slots on the OptiX OSN 550

SLOT

9

(PIU)

SLOT 7 (CST/CSH)

SLOT 1 (EXT )

SLOT 5 (EXT)

SLOT 3 (EXT)

SLOT 2 (EXT )

SLOT 4 (EXT)

SLOT 6 (EXT)

SLOT 8 (CST/CSH)SLO

T10

(PIU)

SLOT11

(FAN)SLOT

92

(PIU)

SLOT 7

2.5Gbit/s

SLOT 5

SLOT 3

SLOT 2

SLOT 4

SLOT 6

SLOT 8 SLOT

91

(PIU)SLOT

93

(FAN)

SLOT 1 2.5Gbit/s

2.5Gbit/s 2.5Gbit/s

1.25Gbit/s 1.25Gbit/s

2.5Gbit/s 2.5Gbit/s

NOTE

l The maximum access capacity of any of slots 1, 2, 3, and 4 is 2.5 Gbit/s but the boards in the four slotscannot all provide an upstream bandwidth of 2.5 Gbit/s at the same time.

l If both boards in slots 1 and 2 provide an upstream bandwidth of 2.5 Gbit/s, slots 3 and 4 cannot houseany TDM service boards.

l If both boards in slots 3 and 4 provide an upstream bandwidth of 2.5 Gbit/s, slots 1 and 2 cannot houseany TDM service boards.

5.2 Outdoor CabinetThe equipment operating in a high-temperature and dust-concentrated outdoor environmentneeds to be installed in an outdoor cabinet.



82

The OptiX OSN 550 can be installed in APM30H outdoor cabinet, For the details of APM30H,see Outdoor Cabinet in Hardware Description.

5.3 Board CategoryThis section describes the boards that the equipment supports. Different boards provide theequipment with different functions.

Table 5-4 lists the boards that the OptiX OSN 550 supports.



83

Table 5-4 Boards that the OptiX OSN 550 supports

BoardClassification

BoardAcronym

BoardName

Port Type ValidSlot

Systemcontrol,switching,and timingboard(Hybrid)

TNM1PCXLX

The cross-connect,timing,systemcontrol, andline boardsupports:l A packet

switchingcapacityof 60Gbit/s

l A higherordercross-connectcapacityof 20Gbit/sand alowerordercross-connectcapacityof 5 Gbit/s

l One10GE andone STM-N ports

l Systemcommunicationandcontrol

l One Ethernet NM port/NM serialport (sharing one RJ45 port)

l One STM-1/STM-4/STM-16small form-factor pluggable(SFP) optical port. The opticalport type can be S-1.1, L-1.1,L-1.2, S-4.1, L-4.1, L-4.2,S-16.1, L-16.1, or L-16.2.

l One 10GE XFP optical port:10GBASE-SR (LAN),10GBASE-SW (WAN),10GBASE-LR (LAN),10GBASE-LW (WAN),10GBASE-ER (LAN),10GBASE-EW (WAN),10GBASE-ZR (LAN), or10GBASE-ZW (WAN)

Slots 7 and8



84

BoardClassification

BoardAcronym

BoardName

Port Type ValidSlot

TNM1PCXX




l One10GEport



l One 10GE XFP optical port:10GBASE-SR (LAN),10GBASE-SW (WAN),10GBASE-LR (LAN),10GBASE-LW (WAN),10GBASE-ER (LAN),10GBASE-EW (WAN),10GBASE-ZR (LAN), or10GBASE-ZW (WAN)

Slots 7 and8



85

BoardClassification

BoardAcronym

BoardName

Port Type ValidSlot

TNM1PCXLG




l One GEand oneSTM-Nports



l One STM-1/STM-4/STM-16small form-factor pluggable(SFP) optical port. The opticalport type can be S-1.1, L-1.1,L-1.2, S-4.1, L-4.1, L-4.2,S-16.1, L-16.1, or L-16.2.

l One GE SFP optical port:1000BASE-SX/1000BASE-LX/1000BASE-VX/1000BASE-ZX

Slots 7 and8



86

BoardClassification

BoardAcronym

BoardName

Port Type ValidSlot

TNM1PCXGA




l One GEport




Slots 7 and8



87

BoardClassification

BoardAcronym

BoardName

Port Type ValidSlot

TNM1PCXGB




l One GEport




Slots 7 and8

Systemcontrol,switching,and timingboard(TDM)

TNM1CXL1

The cross-connect,timing,systemcontrol, andline boardsupports:l A higher

ordercross-


l One STM-1 SFP optical port. Theoptical port type can be S-1.1,L-1.1, or L-1.2.

Slots 7 and8

TNM1CXL4


l One STM-4 SFP optical port ofthe S-4.1, L-4.1, or L-4.2 type

Slots 7 and8



88

BoardClassification

BoardAcronym

BoardName

Port Type ValidSlot

TNM1CXL16

connectcapacityof 20Gbit/sand alowerordercross-connectcapacityof 5 Gbit/s



l One STM-16 SFP optical port ofthe S-16.1, L-16.1, or L-16.2 type

Slots 7 and8

Packetprocessingboard

TNM1MD1

32xsmart E1serviceprocessingboard

75/120-ohm E1 port Slots 1 to 6

TNM1EM6T

6xRJ45 FE/GEprocessingboard

l Four FE electrical ports:10/100BASE-T(X)

l Two GE electrical ports (they canserve as FE electrical ports):1000BASE-T

Slots 1 to 6

TNM1EM6F

4xRJ45 and2xSFP FE/GEprocessingboard

l Four FE electrical ports:10/100BASE-T(X)

l Two GE/FE SFP optical/electrical ports: 1000BASE-SX/1000BASE-LX/1000BASE-VX/1000BASE-ZX/1000BASE-T/100BASE-BX/100BASE-FX/100BASE-LX/100BASE-VX/100BASE-ZX

Slots 1 to 6

TNM1EG4C

4xGE (SFP/RJ45)processingboard

l Four GE electrical ports:1000BASE-T

l Four GE/FE SFP optical ports:1000BASE-SX/1000BASE-LX/1000BASE-VX/1000BASE-ZX/100BASE-BX/100BASE-FX/100BASE-LX/100BASE-VX/100BASE-ZX

Slots 3 to 6



89

BoardClassification

BoardAcronym

BoardName

Port Type ValidSlot

TNM1EF8F

8xFEprocessingboard

l Eight FE SFP optical/electricalports: 100BASE-BX/100BASE-FX/100BASE-LX/100BASE-VX/100BASE-ZX/100BASE-T

Slots 1 to 6

TNM1EX1

1x10GEprocessingboard

One 10GE XFP optical port:10GBASE-SR (LAN), 10GBASE-SW (WAN), 10GBASE-LR (LAN),10GBASE-LW (WAN), 10GBASE-ER (LAN), 10GBASE-EW (WAN),10GBASE-ZR (LAN), or10GBASE-ZW (WAN)

Slots 1 and2 (An EX1boardcannotwork witha PCXGAboard.)

TNM1CQ1

4-portchannelizedSTM-1serviceprocessingboard

l Four STM-1 SFP optical/electrical ports of the S-1.1,L-1.1, or L-1.2 optical type or ofSFP electrical modules

Slots 1 to 6

SDH board TNH2SL1D

2xSTM-1interfaceboard

Two STM-1 SFP optical ports. Theoptical port type can be S-1.1, L-1.1,or L-1.2.

Slots 1 to 6

TNH2SL1Q


Four STM-1 SFP optical ports. Theoptical port type can be S-1.1, L-1.1,or L-1.2.

Slots 1 to 6

TNH2SL4D


Two STM-4 SFP optical ports of theS-4.1, L-4.1, or L-4.2 type

Slots 1 to 6

PDH board TNH2SP3D

42xE1/T1tributaryboard

Forty-two 75/120-ohm E1 ports orforty-two 100-ohm T1 ports

Slots 1 to 6

TNH2PL3T

3xE3/T3tributaryboard

Three 75-ohm E3/T3 ports Slots 1 to 6

EoS board TNH2EFS8

8xFEswitchingandprocessingboard

Eight FE electrical ports:10/100BASE-T(X)

Slots 1 to 6

TNH2EGT1

1xGEtransparenttransmissionboard

One GE SFP optical/electrical port:1000BASE-SX/1000BASE-LX/1000BASE-VX/1000BASE-ZX/1000BASE-T

Slots 1 to 6



90

BoardClassification

BoardAcronym

BoardName

Port Type ValidSlot

TNM1EGS4

4xGEswitchingandprocessingboard

Four GE/FE SFP optical/electricalports: 1000BASE-SX/1000BASE-LX/1000BASE-VX/1000BASE-ZX/1000BASE-T/100BASE-BX/100BASE-FX/100BASE-LX/100BASE-VX/100BASE-ZX

Slots 1 to 6

WDM board TNM1DMD2

2-port opticaladd/dropmultiplexingboard

l wIN/wOUTl wA1/wA2l wD1/wD2l eIN/eOUTl eA1/eA2l eD1/eD2

slot 1 to 6

Auxiliaryboard

TNM1AUX

Auxiliaryinterfaceboard

l One orderwire phone portl One asynchronous data portl One synchronous data portl 6-input/2-output alarm portl One 2-channel external clock

portl Two 2-channel external time

ports

Slots 1 to 6

TNM1FAN

Fan board N/A Slot 93

Powersupplyboard

UPM Uninterruptible powermodule

l One 110 V/220 V AC powerinput port

l Two -48 V DC power outputports

Slot 97

TND1PIU

Powersupply board

One -48 V/-60 V DC power inputport

Slots 91and 92

TNF1APIU

Powersupply board

Two 110 V/220 V AC power inputports

l Slots 4and 6(recommended)

l Slots 2and 4



91

6 Networking and Application Scenarios

About This Chapter

The OptiX OSN 550 supports various service networking topologies in the time divisionmultiplexing (TDM) and packet domains, applicable to a wide range of scenarios.

6.1 Basic Network TopologiesOptiX OSN 550s can form the following network topologies: chain, ring, tangent rings, and ringwith chain.

6.2 Typical Application of Hybrid NetworkingIn Hybrid networking mode, the OptiX OSN 550 can transport packet services and time divisionmultiplexing (TDM) services at the same time.

6.3 Typical Application of Pure Packet NetworkingThis section describes the typical application of pure packet networking.

6.4 Typical Application of TDM NetworkingThis section describes the typical application of time division multiplexing (TDM) networking.

OptiX OSN 550 Multi-Service CPE Optical TransmissionSystemProduct Description 6 Networking and Application Scenarios


92

6.1 Basic Network TopologiesOptiX OSN 550s can form the following network topologies: chain, ring, tangent rings, and ringwith chain.

The OptiX OSN 550 supports separate and combined configurations of the following types:terminal multiplexer (TM), add/drop multiplexer (ADM), and multiple add/drop multiplexer(MADM).

OptiX OSN 550s can support a wide range of network topologies. In addition, OptiX OSN550s can be interconnected with other OptiX OSN equipment, OptiX DWDM equipment, andOptiX Metro equipment to provide a complete transport network solution. See Table 6-1.

Table 6-1 Network topologies supported by OptiX OSN 550s and corresponding legends

Network Topology Legend

Chain

Ring

Tangent rings

Intersecting rings



93

Network Topology Legend

Ring with chain

6.2 Typical Application of Hybrid NetworkingIn Hybrid networking mode, the OptiX OSN 550 can transport packet services and time divisionmultiplexing (TDM) services at the same time.

Figure 6-1 shows a Hybrid ring network, on which the following base station services aretransmitted:

l 2G base station services

l 3G ATM base station services

l 3G IP base station services

Figure 6-1 Hybrid networking

OptiX OSN 550 BTSNodeB BSCRNCOptiX OSN 3500/7500 II

E1/T1

ATM/IMA E1

FE

E1/STM-1

ATM/IMA E1/GE

Packet ring

TDM ring

Signal flow

Networking Solution

When numerous E1 services and Ethernet services coexist, the Hybrid networking solutionmixing the SDH technology and PTN technology is used to meet multi-service transmissiondemands and improve the price performance ratio of network buildout and maintenance.

l E1 services are transmitted in pure TDM mode over the SDH network, which reduces thenetwork buildout and maintenance expenditure.



94

l FE services and GE services are transmitted in pure packet mode over the PTN network,which reduces the transmission expenditure per bit.

l WDM colored optical ports and built-in optical add/drop multiplexers are used when opticalfiber resources are over-consumed or inadequate.

Service Typesl 2G base station services and 3G ATM base station services are transmitted to the OptiX

OSN 550 in TDM E1/T1 mode and ATM/IMA E1 (or PWE3) mode respectively. Theseservices are then mapped to VC-12s and transmitted over the SDH network in end-to-endmode. Finally, these services are aggregated to the OptiX OSN 3500/7500 II that isconnected to the BSC.

l 3G IP base station services are transmitted to the OptiX OSN 550 in FE mode, andencapsulated into PWE3 packets. The PWE3 packets are then aggregated to the OptiX OSN3500/7500 II that is connected to the RNC in end-to-end mode.

Table 6-2 lists the service types and their transmission modes.

Table 6-2 Service types and their transmission modes for a Hybrid network

UNI-sideDevice

Service Port EncapsulationMode

TransmissionTechnology

ServiceTopology

2G base station TDM E1/T1 VC SDH VC P2Pconnection

3G ATM basestation

ATM/IMA E1 VC SDH VC P2Pconnection

3G IP basestation

FE PWE3 MPLS/MPLS-TP

VPWS, VPLS

NOTE

l A 3G base station and an RNC exchange services, base station management information, and signaling.Base station management information and signaling due to their importance are preferentiallyprocessed in the transmission network. Therefore, base station management information and signalingare assigned a VLAN called the management VLAN, and services are assigned a VLAN called theservice VLAN. The management VLAN has a higher priority than the service VLAN.

l To prevent VLAN conflicts, VLANs must be planned by considering all base stations. Generally, thebase stations managed by the same RNC are grouped into multiple switch areas. All base stations inthe same switch area share one management VLAN and one service VLAN. Base stations in differentswitch areas have different management VLANs and service VLANs. See Figure 6-2.

l On the same OptiX OSN 550, the management VLAN and service VLAN are mapped to differentPWs, and the PWs are carried by the same tunnel to save label resources.



95

Figure 6-2 VLAN plan

Switch area 1:Management VLAN=68, Pri=6Service VLAN=78, Pri=4



RNC

Transmission network

NodeB NodeB NodeB

Protectionl The SDH network is protected by the subnetwork connection protection (SNCP) or MSP

mechanism.l The PTN network is protected by the PW 1:1 APS or tunnel 1:1 APS mechanism. To achieve

dual-homing at the convergence layer, a 1:1 APS protection group with the same sourcebut different sinks needs to be configured, as shown in Figure 6-3.



96

Figure 6-3 PW/Tunnel 1:1 APS


Protection channel

Working channel

PW

Tunnel

Co-sourced but not co-sinked 1:1 PW APS

Co-sourced but not co-sinked 1:1 tunnel APS

OAMThe OptiX OSN 550 supports the hierarchical OAM functions for PTN networks, including ETHOAM, MPLS OAM, and MPLS-TP OAM. Figure 6-4 shows the application of hierarchicalOAM.



97

Figure 6-4 Application of hierarchical OAM on a Hybrid network

CE1

CE2

PE1

CE4

CE3

P

P

P

P

P

PE2


MPLS/MPLS-TP PW OAM


ETH Layer

PW Layer

Tunnel Layer

MEP

MEP

MEP MEP

MEP

MEP

MIP MIP


NOTE

For higher network bandwidth utilization, generally only CC/CV OAM is enabled for a tunnel. In addition,to limit tunnel APS protection switching within 50 ms, the detection packet transmission interval is set to3.3 ms.

QoSAs the service access node, an OptiX OSN 550 is generally connected to multiple base stations.Each base station has different priorities of management data and service data. The quality ofservice (QoS) function is used for managing traffic of different services from different basestations. Table 6-3 lists the QoS functions for the OptiX OSN 550.

Table 6-3 QoS functions for the OptiX OSN 550 on a Hybrid network

NetworkPosition

Point of Application QoS Function

Ingress node Ingress direction of theUNI port

VUNI ingress policies: traffic classification andcommitted access rate (CAR)

PW ingress CAR for PWs, the VLAN Pri field being mappedto the LSP EXP field

Egress direction of theNNI port

Weighted random early detection (WRED)congestion management, SP+WRR scheduling(SP is short for strict priority and weighted roundrobin for WRR.)

Transit node Ingress direction of theNNI port

Services being transmitted to different priorityqueues based on their LSP EXP fields



98

NetworkPosition



WRED congestion management, SP+WRR or SP+WFQ scheduling (WFQ is short for weightedfair queuing.)

Egress node Ingress direction of theNNI port


Egress direction of theUNI port

WRED, SP+WRR or SP+WFQ scheduling, theLSP EXP field being mapped to the VLAN Prifield

Ingress direction of theUNI port

VUNI ingress policies: traffic classification andCAR

SynchronizationThe SDH clock or synchronous Ethernet clock is used for network-wide synchronization.

l As shown in Figure 6-5, clock synchronization information from the two buildingintegrated timing supplies (BITSs) is injected into the two OptiX OSN 580/7500 II nodeson the aggregation ring. The master BITS provides a higher-priority clock source and theslave BITS provides a lower-priority clock source.

l The base stations derive clock synchronization information from the OptiX OSN 550 bymeans of the retiming E1 clock, synchronous Ethernet clock, or 2M external clock.

Figure 6-5 Clock synchronization on a Hybrid network

BITS Node B

Slave BITSPhysical synchronization route

Physical synchronization protection route

OptiX OSN 550 BTSOptiX OSN 3500/7500 II

ATM/IMA E1/FE/2M

external clock Master BITS

TDM E1



99

6.3 Typical Application of Pure Packet NetworkingThis section describes the typical application of pure packet networking.

Figure 6-6 shows a pure packet network, on which the following base station services aretransmitted:

l 2G base station services

l 3G ATM base station services

l 3G IP base station services

l LTE base station services

Figure 6-6 Pure packet networking

OptiX OSN 550/500 BTSNodeB BSCRNCOptiX OSN

3500/7500 II

E1/T1

ATM/IMA E1

FE

E1/STM-1

ATM/IMA E1/GE

Packet ring

Signal flow

10GES-GW/MME

Aggregation switch Router

Networking Solution

When numerous Ethernet services and a few E1 services coexist, the pure packet networkingsolution using the expenditure-effective PTN technology is used to meet multi-servicetransmission demands and improve the price performance ratio of network buildout andmaintenance.

l FE services and GE services are transmitted in pure packet mode over the PTN network,which reduces the transmission expenditure per bit.

l E1 services are transmitted in TDM/ATM PWE3 mode over the PTN network since theTDM network is unavailable in the pure packet networking solution.

Service Typesl 3G IP base station services are transmitted to the OptiX OSN 550 in FE mode, and

encapsulated into PWE3 packets. The PWE3 packets are then aggregated to the OptiX OSN3500/7500 II in end-to-end mode.



100

l LTE base station services are transmitted to the OptiX OSN 550 in GE mode, andencapsulated into PWE3 packets. The PWE3 packets are then aggregated to the OptiX OSN3500/7500 II in end-to-end mode.

l 2G base station services and 3G ATM base station services are transmitted to the OptiXOSN 550 in TDM E1/T1 mode and ATM/IMA E1 mode respectively. These services arethen encapsulated into PWE3 packets. Finally, the PWE3 packets are aggregated to theOptiX OSN 3500/7500 II in end-to-end mode.


Table 6-4 Service types and their transmission modes for a pure PTN network

UNI-sideDevice



ServiceTopology

3G IP basestation

FE PWE3 MPLS/MPLS-TP

VPWS, VPLS

LTE basestation

GE PWE3 MPLS/MPLS-TP

VPWS, VPLS

2G base station TDM E1/T1 PWE3 MPLS/MPLS-TP

End-to-end P2Pconnection

3G ATM basestation

ATM/IMA E1 PWE3 MPLS/MPLS-TP

End-to-end P2Pconnection

NOTE

l A 3G/LTE base station and an RNC/S-GW/MME exchange services, base station managementinformation, and signaling. Base station management information and signaling due to their importanceare preferentially processed in the transmission network. Therefore, base station managementinformation and signaling are assigned a VLAN called the management VLAN, and services areassigned a VLAN called the service VLAN. The management VLAN has a higher priority than theservice VLAN.

l To prevent VLAN conflicts, VLANs must be planned by considering all base stations. Generally, thebase stations managed by the same RNC/S-GW/MME are grouped into multiple switch areas. All basestations in the same switch area share one management VLAN and one service VLAN. Base stationsin different switch areas have different management VLANs and service VLANs. See Figure 6-7.

l On the same OptiX OSN 550, the management VLAN and service VLAN are mapped to differentPWs, and the PWs are carried by the same tunnel to save label resources.



101

Figure 6-7 VLAN plan




NodeB/eNodeB NodeB/eNodeB NodeB/eNodeB

RNC/S-GW/MME

Transmission network

ProtectionThe PTN network is protected by the PW 1:1 APS or tunnel 1:1 APS mechanism. To achievedual-homing at the convergence layer, a 1:1 APS protection group with the same source butdifferent sinks needs to be configured, as shown in Figure 6-8.



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Figure 6-8 PW/Tunnel 1:1 APS


Protection channel

Working channel

PW

Tunnel

Co-sourced but not co-sinked 1:1 PW APS

Co-sourced but not co-sinked 1:1 tunnel APS

OAMThe OptiX OSN 550 supports the hierarchical OAM functions for PTN networks, including ETHOAM, MPLS OAM, and MPLS-TP OAM. Figure 6-9 shows the application of hierarchicalOAM.



103

Figure 6-9 Application of hierarchical OAM on a Hybrid network

CE1

CE2

PE1

CE4

CE3

P

P

P

P

P

PE2


MPLS/MPLS-TP PW OAM


ETH Layer

PW Layer

Tunnel Layer

MEP

MEP

MEP MEP

MEP

MEP

MIP MIP


NOTE

For higher network bandwidth utilization, generally only CC/CV OAM is enabled for a tunnel. In addition,to limit tunnel APS protection switching within 50 ms, the detection packet transmission interval is set to3.3 ms.

QoSAs the service access node, an OptiX OSN 550 is generally connected to multiple base stations.Each base station has different priorities of management data and service data. The QoS functionis used for managing traffic of different services from different base stations. Table 6-5 lists theQoS functions for the OptiX OSN 550.

Table 6-5 QoS functions for the OptiX OSN 550 on a pure PTN network

NetworkPosition


Ingress node Ingress direction of theUNI port

VUNI ingress policies: traffic classification andcommitted access rate (CAR)

PW ingress CAR for PWs, the VLAN Pri field being mappedto the LSP EXP field


Weighted random early detection (WRED)congestion management, SP+WRR scheduling(SP is short for strict priority and weighted roundrobin for WRR.)

Transit node Ingress direction of theNNI port




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NetworkPosition



WRED congestion management, SP+WRR or SP+WFQ scheduling (WFQ is short for weightedfair queuing.)

Egress node Ingress direction of theNNI port


Egress direction of theUNI port

WRED, SP+WRR or SP+WFQ scheduling, theLSP EXP field being mapped to the VLAN Prifield

Ingress direction of theUNI port

VUNI ingress policies: traffic classification andCAR

SynchronizationThe synchronous Ethernet clock is used for network-wide synchronization.


l The base stations derive clock synchronization information from the OptiX OSN 550 bymeans of the retiming E1 clock, synchronous Ethernet clock, or 2M external clock.

Figure 6-10 Clock synchronization on a pure PTN network

BITS Node B




ATM/IMA E1/FE/2M

external clock Master BITS

TDM E1



105

6.4 Typical Application of TDM NetworkingThis section describes the typical application of time division multiplexing (TDM) networking.

Figure 6-11 shows a TDM network, on which the following base station services are transmitted:

l 2G base station servicesl 3G ATM base station servicesl 3G IP base station services

Figure 6-11 Pure TDM networking

OptiX OSN 550 BTSNodeB BSCRNCOptiX OSN 3500/7500 II

E1/T1

FE

E1/STM-1

GE

TDM ring

Signal flow

Networking SolutionWhen numerous E1 services and a few Ethernet services coexist, the pure TDM networkingsolution using the sophisticated and expenditure-effective SDH technology is used to improvethe price performance ratio of network buildout and maintenance.

l E1 services are transmitted in pure TDM mode over the SDH network, which reduces thenetwork buildout and maintenance expenditure.

l FE services are transmitted in Ethernet over SDH (EoS) mode over the SDH network sincethe PTN network is unavailable in the pure TDM networking solution.

Service Typesl 2G base station services and 3G ATM base station services are transmitted to the OptiX

OSN 550 in TDM E1/T1 mode and ATM/IMA E1 mode respectively. These services arethen mapped to VC-12s and transmitted over the SDH network in end-to-end mode. Finally,these services are aggregated to the OptiX OSN 3500/7500 II that is connected to the BSC.

l 3G IP base station services are transmitted to the OptiX OSN 550 in FE mode. Theseservices are then encapsulated into VC-12s in EoS mode and transmitted over the SDHnetwork in end-to-end mode. Finally, these services are aggregated to the OptiX OSN3500/7500 II that is connected to the RNC.



106


Table 6-6 Service types and their transmission modes for a pure TDM network

UNI-sideDevice



ServiceTopology

2G base station TDM E1/T1 VC SDH VC P2Pconnection

3G ATM basestation

ATM/IMA E1 VC SDH VC P2Pconnection

3G IP basestation

FE Ethernet overSDH

SDH EVPL,EVPLAN

ProtectionThe SDH network is protected by the subnetwork connection protection (SNCP) or MSPmechanism.

OAMThe OptiX OSN 550 supports Ethernet port OAM that complies with IEEE 802.3ah and Ethernetservice OAM that complies with IEEE 802.1ag for Ethernet service fault analysis and locating.Figure 6-12 shows the application of ETH OAM.

Figure 6-12 Application of ETH OAM on a pure TDM network


Ethernet Service OAM Ethernet Port OAMEthernet Port OAMETH Layer MEP MEP

NodeB RNC

FE

FEGE

QoSAs the service access node, the OptiX OSN 550 may receive burst Ethernet traffic. Thecommitted access rate (CAR) mechanism must be applied for incoming traffic. Incoming traffic



107

must be scheduled before being transmitted to virtual concatenation (VC) channels, to ensurethat higher-priority services are forwarded first. The QoS function is used for managing trafficof different services from different base stations. Table 6-7 lists the QoS functions for the OptiXOSN 550.

Table 6-7 QoS functions for the OptiX OSN 550 on a pure TDM network

NetworkPosition


Access node Ingress direction of theUNI port

Traffic classification, committed access rate(CAR), priority-based scheduling

Aggregation node Ingress direction of theUNI port

Traffic classification, CAR, priority-basedscheduling

SynchronizationThe SDH clock is used for network-wide synchronization.


l The base stations derive clock synchronization information from the OptiX OSN 550 bymeans of the retiming E1 clock or 2M external clock.

Figure 6-13 Clock synchronization on a pure TDM network

BITS Node B




ATM/IMA E1/2M external

clockMaster BITS

TDM E1



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7 Network Management System

About This Chapter

The OptiX OSN 550 is uniformly managed by the transmission network management system(NMS) and local craft terminal (LCT) through the ETH port. The OptiX OSN 550 supports theSimple Network Management Protocol (SNMP).

The NMS maintains the OSN, SDH, Metro, and DWDM network elements (NEs) on an entirenetwork. The NMS can implement end-to-end configurations for packet and TDM services.

The OptiX OSN 550 complies with ITU-T Recommendations. The equipment adopts amanagement information model and an object-oriented management technology. With the NMS,the equipment can exchange information with the NE software through the communicationmodule to manage alarms and performance events in a centralized manner. In addition, end-to-end configuration on the management plane can be achieved.

The OptiX OSN 550 supports SNMPv2/SNMPv3, which allows a third-party NMS to monitorequipment performance.

7.1 Network ManagementThis chapter describes the network management system, inter-NE communication management,and intra-NE communication management.

7.2 DCN ManagementReliable network management ensures proper running of a network, and therefore transmissionof network management data becomes very critical. The data communication network (DCN)is a network management data communication channel, with which users can remotely manageand maintain NEs.

7.3 Synchronization Between the NMS and NEsWith the time synchronization function, consistency is maintained between the NE time and theU2000 server time. In this way, the U2000 is able to record the correct time at which alarmsoccur and the correct time at which the abnormal events are reported by NEs.

OptiX OSN 550 Multi-Service CPE Optical TransmissionSystemProduct Description 7 Network Management System


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7.1 Network ManagementThis chapter describes the network management system, inter-NE communication management,and intra-NE communication management.

Figure 7-1 shows the typical network management application of the OptiX OSN 550.l Network management system: U2000 and U2000 LCTl Inter-NE communication management:

– The NEs at sites A and C are gateway NEs (GNEs) and are connected to the externalDCN through a switch or router. All the other NEs are non-GNEs that communicatewith the NMS through GNEs.

– The NEs between sites A and D are connected with fibers and use the HWECC or IPover DCC protocol to exchange information over ESC/OSC channels.

– The NEs between sites E and C are connected with fibers and use the HWECC or IPover DCC protocol to exchange information over ESC channels.

– The NEs between sites F and C are connected with fibers and use the HWECC or IPover DCC protocol to exchange information over inband channels.

– Some NEs between sites A and F (NEs connected to an optical or electrical transmissiondevice, such as NEs at site B) are connected with network cables, and use the HWECCor IP over DCC protocol to exchange information over Ethernet channels (at NM_ETHports).

l Intra-NE communication management: The master and slave subracks implement intra-NEcommunication for each NE at sites A-D. One NE at site A has three subracks (one masteris connected to two slaves).



110

Figure 7-1 Network management

External DCN

Secondary U2000

Fiber Network cable

NON-GNE

SwitchRouter

Site B

U2000 Web LCT

Primary U2000

GNE

Subrack

Master

Slave Slave

Site D

Site CSite A

Site F

Site E

NON-GNE

GNE

NON-GNE

NON-GNE

OptiX OSN 8800 OptiX OSN 550/500OptiX OSN 1800

NOTE

Figure 7-1 illustrates a network that has Huawei equipment deployed at different layers: NEs at sites A-D are OptiX OSN 8800 NEs, NEs at site E are OptiX OSN 1800 NEs, and NEs at site F are OptiX OSN550/500 NEs.

Network management involves the following aspects:

Network Management SystemThe network management system (NMS) provides unified management for OptiX equipment.In compliance with associated ITU-T Recommendations, the NMS uses a standard informationmanagement model and object-oriented management technology.

The NMS manages alarms, performance, configurations, communication, security, andtopologies of the entire optical transmission system. The NMS also gives users end-to-endmanagement capabilities. An NMS helps to improve network quality, lower maintenanceexpenditures, and ensure efficient utilization of network resources.

The NMS includes two sets of network management software: iManager U2000 (U2000) andiManager U2000 LCT (U2000 LCT). The U2000 is usually installed at a network managementcenter, and most equipment is managed remotely. The LCT provides the ability to configure andmaintain individual NEs. The LCT is usually installed on a PC for local access to equipment.

Inter-NE Communication ManagementInter-NE communication management is implemented based on data communication networks(DCNs). A DCN consists of NMSs, GNEs, non-GNEs, and the connections between them. Both



111

NMSs and NEs are nodes of a DCN. The DCN between the NMSs and NEs is called the externalDCN, and the DCN between NEs is called the internal DCN.

l An external DCN is a local area network (LAN) or a wide area network (WAN) and usesthe TCP/IP protocol for communication. It provides communication between NMSs andbetween the NMS server and GNEs.

l An internal DCN uses the HWECC or TCP/IP protocol to provide communication betweenNEs. NEs support inband DCN and outband DCN. The outband DCN uses DCC overheadbytes as physical DCN channels. The inband DCN uses Ethernet service channels asphysical DCN channels.

7.2 DCN ManagementReliable network management ensures proper running of a network, and therefore transmissionof network management data becomes very critical. The data communication network (DCN)is a network management data communication channel, with which users can remotely manageand maintain NEs.

Table 7-1 lists the DCN solutions that the OptiX OSN 550 supports.

Table 7-1 DCN solutions that the OptiX OSN 550 supports

Item Inband DCN Outband DCN

Purpose andbenefit

NM information is transmittedthrough the service channelsprovided by managed equipment.Therefore, no extra equipment orDCN is required. This reducesoperating expenditure.

NM information is transmitted onnon-service channels.

Feature l Flexible networking: NMinformation is encapsulated intoEthernet frames and carries afixed VLAN ID to get separatedfrom the service data. The NMinformation is transmitted withservices on service channels.

l Configurable VLAN prioritiesfor inband DCN packets

High reliability: Outband DCN usesdedicated maintenance channels.Therefore, an NMC can construct aDCN network with managedequipment in various ways, such asE1 private lines and Ethernet; inaddition, you can obtain NMinformation in time even whenfaults occur on service channels.

Networkingtechnology

l HWECCl IP

l HWECCl IPl OSI

Applicationscenario

Packet network TDM network

Resourceallocationmode

N/A Channel types: D1-D3



112

Item Inband DCN Outband DCN

Running mode:l Mode 1: 32 channels using D1-

D3 bytesl Mode 2: 12 channels using D1-

D3 bytes or 6 channels using D4-D12 bytes

7.3 Synchronization Between the NMS and NEsWith the time synchronization function, consistency is maintained between the NE time and theU2000 server time. In this way, the U2000 is able to record the correct time at which alarmsoccur and the correct time at which the abnormal events are reported by NEs.

When NEs report alarms and abnormal events to the U2000, the time at which such alarms andevents occur is based on the NE time. If the NE time is incorrect, then the wrong time with regardto the occurrence of alarms is recorded in the U2000. This may cause trouble in fault location.In addition, the wrong time with regard to the occurrence of abnormal events is recorded in theNE security logs. To ensure the NE time accuracy, the U2000 provides three timesynchronization schemes: synchronizing with the U2000 server, synchronizing with the NTPserver and synchronizing with the standard NTP server and synchronizing with the standardNTP server.

l If you use the scheme of synchronizing with the U2000 server, all NEs use the U2000 servertime as the standard time. The NE time can be synchronized with the U2000 server timemanually or automatically. The U2000 server time refers to the system time of theworkstation or computer where the U2000 server is located. This scheme features easyoperation, and is applicable in networks that require a low accuracy with regard to time.

l If you use the scheme of synchronizing with the NTP server or synchronizing with thestandard NTP server, the NE time and the U2000 time are synchronized with the NTP servertime or the standard NTP server time automatically. The NTP server can be the U2000server or a special time server. This scheme enables the U2000 and NEs to have a timeaccuracy of one nanosecond in theory, and applies to a network with high requirement fortime accuracy.

NTP Network ApplicationFigure 7-2 shows a network in which NTP is used to ensure synchronization across the network.



113

Figure 7-2 Network using NTP to ensure synchronization

Time server

NMS server

NE1

NE5 NE4

NE3

NE2

The highest-level time server

Clients

The middle-level time server

As shown in Figure 7-2, the equipment in the network can be classified into three categories:

l The highest-level time server: the 0-level time serverl The middle-level time server: the 1- or 2-level time server that obtains time information

from the higher-level time server and provides time information for the lower-level timeserver

l Clients: obtaining time information only

In application, the server and clients can be configured as follows:

l Choose the NMS server as the time server for NEs. The NMS server can be set as thehighest-level time server, or set to obtain time information from other time servers.

l NEs can only be set as the client, obtaining time information from the specified time server.



114

8 Operation and Maintenance

About This Chapter

Routine equipment maintenance and troubleshooting are essential to ensure that a network runsproperly. The OptiX OSN 550 provides strong maintenance capabilities.

Table 8-1 Functions for deployment and configuration

Function Description

Automatic search foroptical fibers

Supports the fiber auto-discovery function on the NMS.

OptiX OSN 550 Multi-Service CPE Optical TransmissionSystemProduct Description 8 Operation and Maintenance


115

Table 8-2 Routine maintenance functions


Alarm andperformancemanagement

l Provides audible and visual alarms warn of emergencies to helpnetwork administrators take prompt action.

l Provides running status indicators and alarm indicators on allboards to help administrators locate and handle faults quickly.

l Provides the alarm input and output function to facilitate alarmcollection for external devices.

l Dynamically monitors the operation and alarm status of all NEsusing the NMS.

l Detects alarms and performance of a standby system controlboard.

l Stores results of sixteen consecutive 15-minute performancemonitoring events, that is, four hours of performance eventsdivided into 15-minute segments.

l Stores results of six consecutive 24-hour performance monitoringevents, that is, six days of performance events divided into 24-hour segments.

RMON Monitors data from different network segments on a transmissionnetwork. RMON supplements simple Ethernet performancemanagement tools, and can be used on a wide range of networks.

Voltage check Measures input voltages and detects undervoltage and overvoltagestates.

Automatic lasershutdown (ALS)

l SDH single-mode optical ports support the ALS function.l Packet Ethernet boards support the setting of upper threshold or

lower threshold of input optical power.

Port impedance query Supports the query of port impedance on the NMS.

Optical moduleinformation query

Allows the NMS to query information about optical modules,including single-mode/multi-mode, rate level, supplier, productiondate, and wavelength.

Outdoor cabinetmonitoring

Monitors outdoor cabinets by means of the monitoring ports on AUXboards.

Power consumptioncontrol

l Computes system power consumption.l Monitors the total power consumption of an NE, and reports an

alarm if the total power consumption exceeds the powerconsumption threshold of the NE.

l Supports the query of the power consumption of an NE/board byusing the NMS.

Storage of the ID andIP address of an NE

The backplane stores IDs and IP addresses of NEs, and the activeSCC board reads these from the backplane.



116


Port informationquery

Queries communication protocols in use, status, functions, andnames of ports used for external communication and physical portsconnected to networks.

Table 8-3 Fault diagnosis functions


ETH OAM Uses outband packets to detect and monitor the connectivity andperformance of service trails. The process does not affect services.

ATM OAM Detects and locates ATM faults, and monitors ATM performance.

MPLS OAM l Detects and locates faults on an MPLS network, and works withMPLS APS to protect services.

l MPLS OAM mechanisms include tunnel OAM and PW OAM.Tunnel OAM operates at the tunnel layer, and PW OAM operatesat the PW layer.

MPLS-TP OAM l MPLS-TP OAM can detect, identify, and locate faults on packetswitched networks, and notify NEs of the faults, so the NEs canimplement protection switching.

l MPLS-TP OAM mechanisms include tunnel OAM and PWOAM. Tunnel OAM operates at the tunnel layer, and PW OAMoperates at the PW layer.

One-click datacollection

l Provides a one-click data collection function for fault data toreduce data collection time before service recovery.

l Users can collect fault data selectively and can stop a collectionprocess manually.

Loopback Service boards support inloops and outloops on ports to facilitatefault location.

Remote maintenance Maintenance personnel can use a public telephone network toremotely maintain the OptiX OSN 550 equipment.

PRBS l An NE enabled with the PRBS function can be used as aninstrument to transmit and receive unframed services in order toanalyze whether service paths are faulty.

l An NE enabled with the PRBS function can be used to analyzeitself or the entire network.

l The PRBS function substitutes for a test instrument duringdeployment or fault location.

Warm/Cold resets System control, switching, and timing boards and service boardssupport warm and cold resets. Warm resets do not affect services.



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Hot swap l Service boards, system control, switching, and timing boards,power supply boards, and fan boards support hot swapping.

l Pluggable optical modules can be hot-swapped.l Service cables and auxiliary cables can be hot-swapped.

Port mirroring Supports port mirroring that enables Ethernet service testing andservice fault diagnosis without affecting the services.

Disaster recovery forNE configuration data

Restores NE data using a configuration file downloaded from theNMS. A traditional NE database backup may end up with a failure.Disaster recovery for NE configuration data uses NMS configurationdata as the data restoration source to rebuild NE configurationdatabase. This function applies to the following scenarios:l An NE is down and its database needs to be rebuilt.l A few services carried by an NE are interrupted. The NE cannot

be configured and there is no valid database backup file.l Many services carried by an NE are interrupted. The NE cannot

be configured, or can be configured but the configuration processis too long. Furthermore, there is no valid database backup file.

NOTICEDownloading configuration data from the NMS is highly risky and thisoperation must be performed under the on-site guidance of a Huawei engineer.After an NE database on a live network is damaged, conventional maintenancemethods are preferred, such as manual recovery and database restoration usinga DC tool.

Alarm reporting uponremoval of importantperipheral storagedevices

When a CF storage card is removed, the equipment reports a securityalarm.

NSF NSF stands for Non-interrupted Service Forwarding. When thecontrol plane of the equipment is faulty, the NSF function ensuresthat the data services are not interrupted, ensuring transmission ofthe key services on the network.

Table 8-4 Functions for upgrades


Upgrade and loadingof board software andNE software

l Supports in-service upgrades and loading of board software andNE software.

l Supports remote loading of board software and fieldprogrammable gate array (FPGA).

l Supports error-proof loading and resumable loading.



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Hot patch loading Supports the hot patch loading function. Running software can beupgraded without being interrupted.

Software packageloading

Software package loading enables NE and board software to beloaded to an NE at a time. OptiX OSN 580 supports customizedpackage loading, which prevents the problem of insufficient storagespace from occurring during an upgrade.

8.1 Maintenance Support (Packet)This section describes the maintenance functions and features in the packet domain.

8.2 Maintenance Support (TDM)This section describes the maintenance functions and features in the TDM domain.

8.3 Upgrade MethodsIf the current version of the OptiX OSN 550 cannot meet customer requirements, upgrade theequipment to a higher version. The available upgrade methods are package loading and packagediffusion.



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8.1 Maintenance Support (Packet)This section describes the maintenance functions and features in the packet domain.

8.1.1 TP-AssistWith the explosive growth of service traffic, metropolitan area networks (MANs) now mainlycarry data services, such as video services, Internet services, and voice over IP (VoIP) services,instead of traditional voice services. Compared with connection-oriented SDH networks, packetswitched networks (PSNs) feature more flexible networking, complex configurations, and highertechnical requirements on operation and maintenance personnel. TP-Assist dramaticallysimplifies PSN operation and maintenance, facilitating deployment of large-scale networks.

Unlike an SDH network, a packet network brings the following challenges:

l More types of network topologies and more complex and time-consuming configurations,which impose higher requirements on O&M personnel.

l Lack of overheads that indicate the physical status of a network to real-time monitorservices or form a complete alarm system. Once a network is faulty, it is hard to locate thefault.

TP-Assist supports a wide variety of transmission devices, complies with OAM standards, andintegrates Huawei's powerful NMS U2000 and unique operation and maintenance experience.It applies to all stages of the network life cycle.

TP-Assist

Network planning

Network topology planning

Service and hardware configuration planning

Service configuration

End-to-end service deployment

Automatic deployment of alarm management

Service commissioning

One-click service connectivity test

One-click service performance test

Automatic test with no need for any instrument

Routine maintenance

Performance monitoring and statistics

Fault diagnosis

Intelligent fault diagnosis

IP ping response

Service loop detection

Service path visualization

l Network planning: provides powerful network planning tools and professional networkplanning service.

l Service configuration:

– Deploys services across microwave and optical fibers in an end-to-end manner.

– Automatically deploys alarm management when services are being deployed,simplifying alarm deployment. Alarms can be reported upon a service interruption.

l Service commissioning:

– Provides one-click service connectivity and performance tests.

– Automatically tests the delay, throughput, and packet loss rate with no need for any testinstruments.



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l Routine maintenance: monitors performance and collects performance statistics by port,flow classification, VLAN, VUNI, VUNI group, PW, tunnel, and queue priority.

l Fault diagnosis:

– Provides the quick fault diagnosis function, which diagnoses faults at the service, PW,or tunnel layer by checking connectivity, performance, and configurations.

– Provides the IP ping function to test end-to-end connectivity, facilitating quick faultlocation.

– Locates looped points, checks whether a loop forms due to incorrect serviceconfigurations, and automatically disables looped services in a ring network storm,therefore minimizing the impact of looped services on the network.

8.1.2 MPLS OAMThe MPLS OAM mechanism supported by the equipment includes tunnel OAM and PW OAM.Tunnel OAM operates at the tunnel layer, and PW OAM operates at the PW layer. Tunnel OAMand PW OAM both provide the complete fault detection and locating mechanism.

Tunnel OAMl Description

The tunnel OAM mechanism helps to effectively detect, identify, and locate internal defectsat the tunnel layer of an MPLS network. The equipment triggers the protection switchingbased on the OAM detection status. Therefore, quick fault detection and service protectioncan be achieved.

l Objectives and benefits

As a key bearer technology for the scalable next generation network (NGN), MPLSprovides multi-service capabilities with ensured QoS. In addition, MPLS introduces aunique network layer (tunnel), which may cause some faults. Therefore, an MPLS networkmust have the OAM capability.

By providing a tunnel OAM mechanism independent of any upper layer or lower layer, thetunnel OAM supports the following features:

– Provides query-on-demand and consecutive detections so that at any moment you canlearn whether the monitored tunnel has defects.

– Detects, analyzes, and locates any defect that occurs, and notifies the NMS of therelevant information.

– Triggers a protection switching immediately after a defect or fault occurs on a link.

– Monitors the performance events indicating packet loss ratio, delay, and jitter in realtime and reports them to the NMS.

PW OAMl Description

The PW OAM mechanism helps to effectively detect, identify, and locate internal defectsat the PW layer of a network. The equipment triggers the protection switching based on theOAM detection status. Therefore, quick fault detection and service protection can beachieved.

l Objectives and benefits



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The equipment performs PW encapsulation on service packets, and then transmits theservice packets over tunnels. The network consists of two layers: tunnel and PW. Tunnelsuse tunnel OAM for maintenance and management, and PWs use PW OAM formaintenance and management. Currently, the equipment can detect the connectivity of acertain PW through ping packets, and then reports the result to the NMS.

8.1.3 MPLS-TP OAMMPLS-TP OAM is defined by MPLS-TP. It is compatible with existing MPLS OAM standardsand focuses on particularity of transport networks.

MPLS-TP OAM is available in two technical solutions: solution based on bidirectionalforwarding detection (BFD) extension and solution based on ITU-T G.8113.1. This sectiondescribes the solution based on ITU-T G.8113.1 extension.

ITU-T G.8113.1-compliant MPLS-TP OAM applies to most data communication equipmentand packet switching equipment, and therefore can provide end-to-end OAM for PSNsconsisting of data communication equipment and packet switching equipment.

Figure 8-1 Application of MPLS-TP OAM on a PSN consisting of data communicationequipment and packet switching equipment

RNC

RNC

PSN

PW1PW2

MPLS tunnel

NodeB

NodeB

NE1 NE2


MPLS-TP OAM

Equipment with MPLS-TP OAM functionality can meet carrier-class data transmission needs.

8.1.4 ETH OAMETH OAM enhances Ethernet Layer 2 maintenance functions and it strongly supports servicecontinuity verification, service deployment commissioning, and network fault locating.

DefinitionBased on the MAC layer, the ETH OAM protocol performs OAM operations for the Ethernetby transmitting OAM packets. This protocol is irrelevant to the transmission medium. The OAM



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packets are processed only at the MAC layer, having no impact on the other layers of the Ethernet.In addition, as a low-rate protocol, the ETH OAM protocol occupies low bandwidths. Therefore,this protocol does not affect services carried on links.

ITU-T and IEEE have researches on ETH OAM. Currently, Huawei Ethernet service processingboards have realized the ETH OAM function, which complies with IEEE 802.1ag and IEEE802.3ah. Wherein, IEEE 802.1ag define Ethernet service OAM standards, and IEEE 802.3ahdefines Ethernet port OAM standards. As shown in Figure 8-2, the combination of IEEE 802.1agand IEEE 802.3ah provides a complete Ethernet OAM solution.

Figure 8-2 Application of IEEE 802.1ag and IEEE 802.3ah

Core Layer

PE1

CE4

PE2

CE3

P

P P

P

CE1

Router3

Access LayerAccess Layer

Custom LayerCustom Layer

Router1

Router2

IEEE 802.3ah

IEEE 802.3ah

CE2

OptiX NE

IEEE 802.1ag

l Ethernet service OAM focuses on the maintenance of end-to-end Ethernet links. Based on

services, Ethernet service OAM implements end-to-end detection in the unit of"maintenance domain" and performs segmental management on each network segment thatis involved in the same service on a network.

l Ethernet port OAM focuses on the maintenance of point-to-point Ethernet link betweentwo directly-connected devices in Ethernet in the first mile (EFM). Ethernet port OAMdoes not focus on a specific service. It maintains the point-to-point Ethernet link byperforming OAM auto-discovery, link performance monitoring, fault check, remoteloopback, and selfloop check.

PurposeWith the continuous development of the Ethernet, especially when LANs evolve to WANs,operators pay more attention to equipment maintainability. Solutions to operations,administration and maintenance (OAM) in the transmission network are required urgently.Therefore, ETH OAM is developed.

A comparison of ETH OAM and existing OAM and fault locating methods is provided asfollows:

l When a loopback is performed at a port, all packets on the port are looped back. Therefore,the loopback method cannot be used if only a specific service needs to be looped back.



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l ETH OAM can detect hardware faults.l ETH OAM can detect and locate faults automatically.

8.1.5 ATM OAMThis section provides the definition of ATM OAM and describes its purpose.

DefinitionATM OAM is used for detecting and locating ATM faults, and monitoring ATM performance.In this document, ATM OAM refers to OAM only at the ATM layer and implements variousOAM functions by means of specific ATM OAM cells.

PurposeATM OAM provides segment-based ATM OAM between the CE and the PE and end-to-end-based ATM OAM between CEs.

As shown in Figure 8-3, ATM OAM cells are transmitted and detected between the CE and thePE, or between the CEs to monitor the ATM link.

Figure 8-3 Typical application of ATM OAM

PE1 PE2

Packet transmissionequipment

CE2CE1(NodeB) (RNC)

Segment check

End-to-end check

Segment check

ATM cell stream (VP level or VC level)

8.1.6 RMONBy using the remote monitoring (RMON), you can transmit network monitoring data betweendifferent network sections.

Currently, the management of the Ethernet performance for transmission products is relevantlysimple. In the case of the management of Ethernet ports, the management of the performancedata of the ports is required. What's more, as the network is becoming complex, a method for



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managing network sections is required. Thus, the RMON emerges and the RMON should havethe following features:l All statistics data is saved at the agent and the out-of-service operation on the manager is

supported.l History data is saved for the fault diagnosis.l Errors are detected and reported.l Detailed data is provided.l Multiple management stations are supported.

Based on the preceding purposes, the RMON defines a serial of statistic formats and functionsto realize the data exchange between the control stations and detection stations that complieswith the RMON standards. To meet the requirements of different networks, the RMON providesflexible detection modes and control mechanism. What's more, the RMON provides errordiagnosis, planning and information receiving of the performance events of the entire network.

8.1.7 PRBSBoards with E1 ports provide the pseudo-random binary sequence (PRBS) functional module,which is used for network self-test and maintenance. You can determine whether the workingchannel on the UNI/NNI side is normal, depending on whether bit errors are detected in a PRBStest.

The PRBS functional module is equivalent to a simple instrument that transmits and receivesunframed services.

Bit errors detected by the PRBS functional module help diagnose the faults on service paths andlocate the faults on fibers or boards. By using the PRBS function, you can analyze the local NEand the entire network. Therefore, you can perform a test without a real instrument during thedeployment or fault locating.

8.1.8 CES Alarm TransmissionThe OptiX OSN equipment uses the L/M and R fields in the control word to transparentlytransmit alarms.

CES alarm transparent transmission involves transmitting local CES alarms to the remote end,and inserting corresponding alarms to notify the remote end of faults in the local end. Dependingon the position where the alarm is generated, CES alarm transparent transmission can be betweenAC sides, and from the NNI side to the AC side.

CES Alarm Transparent Transmission Between AC SidesThere are two scenarios where CES alarms are transparently transmitted between AC sides.

l The fault information on the AC link or port is transmitted through the PSN as follows:



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Figure 8-4 CES alarm transparent transmission between AC sides (1)

PSN

PE1 LSP

PWAC1 AC2


RNCPE2NodeB

If PE1 detects a link fault or an E1 port fault on the AC1 side, PE1 returns RDI to upstreamand informs PE2 of the fault through the L field of control word. Upon receiving the controlword, PE2 reports the CESPW_OPPOSITE_ACFAULT alarm and inserts AIS to the AC2side.

l The service alarms on the AC side are transparently transmitted through the PSN as follows:

Figure 8-5 CES alarm transparent transmission between AC sides (2)

PSN

PE1 LSP

PWAC1 AC2


RNCPE2NodeB

If the RNC detects a link fault or an E1 port fault on the AC2 side, the RNC returns RDIto PE2; PE2 reports the RAI alarm and informs PE1 of the fault through the L/M field ofcontrol word. Upon receiving the control word, PE1 reports the RAI alarm and returns RDIto AC1.

NOTE

The SAToP encapsulation mode does not support the M field, and therefore cannot transparentlytransmit the RAI alarm.

CES Alarm Transparent Transmission from the NNI Side to the AC SideFigure 8-6 shows the CES alarm transparent transmission from the NNI side to the AC side.



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Figure 8-6 CES alarm transparent transmission from the NNI side to the AC side

PSN

PE1 LSP

PWAC1 AC2


RNCPE2NodeB

When detecting that packet loss ratio continuously beyond the preset threshold, PE2 inserts theAIS alarm into AC2, and uses the R field in the control word to transmit the information to PE1.Then, PE1 reports the RAI alarm based on the R field.

8.1.9 Port MirroringFor the existing complex networks, OptiX OSN equipment has already provided variouseffective fault diagnosis methods. However, the methods require path overheads or eveninterrupt service. Therefore, a fast fault diagnosis method that does not affect services is urgentlyrequired. Port mirroring effectively addresses this requirement.

Port mirroring has the following features:

l Port mirroring applies to online fault diagnosis. It replicates the traffic at one port to anotherport, and then an analyzer is used to locate faults.

l After port mirroring is used, traffic can be monitored in real time using an analyzer.

As shown in Figure 8-7, a port on NE1 is the mirror source port and another port on NE1 is themirror destination port. NE1 replicates the traffic at the mirror source port to the mirrordestination port. An analyzer is used to analyze the traffic or to monitor the traffic in real timewithout affecting the services.

Figure 8-7 Typical networking for port mirroring

RNC

NodeB

NE2

Normal Service

Mirror Service

NE3

Analyst

NE1(Monitored/Monitor)

Mirror Source Function Point

Mirror Observation Point



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8.2 Maintenance Support (TDM)This section describes the maintenance functions and features in the TDM domain.

8.2.1 PRBSCertain boards provide the PRBS functional module, which is used for testing and maintainingthe network. You can determine whether the working path on a tributary port, in the linedirection, or in the cross-connect direction is normal, depending on whether bit errors aredetected in a PRBS test.

For details, see PRBS.

8.2.2 ETH OAMETH OAM enhances Ethernet Layer 2 maintenance functions and it strongly supports servicecontinuity verification, service deployment commissioning, and network fault locating.

For details, see ETH OAM.

8.2.3 RMONBy using the remote monitoring (RMON), you can transmit network monitoring data betweendifferent network sections.

For details, see RMON.

8.2.4 Data Test FrameThe test frame is a data packet that is used to test the connectivity status of the network on theSDH side that transmits Ethernet services. The test frame is mainly used for commissioningEthernet services or locating Ethernet service faults.

Configuring test frames does not affect services.

The test frame function complies with the Huawei internal standard, and can be transmitted andreceived only between VCTRUNK ports.

8.3 Upgrade MethodsIf the current version of the OptiX OSN 550 cannot meet customer requirements, upgrade theequipment to a higher version. The available upgrade methods are package loading and packagediffusion.

Table 8-5 lists the upgrade methods available for the OptiX OSN 550.



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Table 8-5 Upgrade methods available for the OptiX OSN 550

UpgradeMethod

Package Loading Package Diffusion

Definition With a software packagedescription file, a software packagefunctions as a logical package ofrequired software. This logicalpackage can be uploaded toupgrade an entire NE.

With a software packagedescription file, a software packagefunctions as a logical package ofrequired software. The logicalpackage is diffused and almostsynchronously loaded to all NEs ona network. This upgrade method ismore efficient.

Applicationscenario

l One NE needs to be upgraded.l System control boards and other

boards must support packageloading.

l There are CF cards on systemcontrol boards.

l More than one NE needs to beupgraded.

l System control boards and otherboards must support packageloading.

l There are CF cards on systemcontrol boards.

Characteristic l All the boards on an NE can beupgraded on a unified GUI.

l There is no need to care aboutwhich boards to upgrade orwhich files to update.

l All the boards on an NE can beupgraded on a unified GUI.

l There is no need to care aboutwhich boards to upgrade orwhich files to update.

l Software packages are diffused.l Network load and network

bandwidth are both shared.

Applicableversion

V100R003C00 and later versionssupport this upgrade method.

V100R003C00 and later versionssupport this upgrade method.



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9 Security Management

About This Chapter

The OptiX OSN 550 allows NE security management to be implemented by various means.

9.1 Authentication ManagementFor security concerns, only an authenticated user can log in to an NE.

9.2 Authorization ManagementAuthorization management allows different authorities for different users when they operate anNE. This effectively protects an NE against inappropriate operations.

9.3 Network Security ManagementThe security of transmitting data between the NMS and NEs, and in networks, is the preconditionfor the NMS to manage the NEs.

9.4 System Security ManagementThe system provides necessary security policies that are executed forcibly.

9.5 Log ManagementThe OptiX OSN 550 supports system security log management and Syslog management.

OptiX OSN 550 Multi-Service CPE Optical TransmissionSystemProduct Description 9 Security Management


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9.1 Authentication ManagementFor security concerns, only an authenticated user can log in to an NE.

l NE login management: You can successfully log in to an NE only after entering the correctuser name and password.

l NE user switching: One client allows only one user to operate an NE at a time. For thisreason, if multiple NE users log in to an NE, the NE users need to be switched to ensurethat the configuration data is unique.

l Forcibly making other NE users exit from the NE: To avoid errors caused by simultaneousconfiguration by multiple users, or to prevent other users from illegally logging in to theNE, one user of system level or debugging level can forcibly make other users exit fromthe NE.

l You can query users that have logged in to an NE.

9.2 Authorization ManagementAuthorization management allows different authorities for different users when they operate anNE. This effectively protects an NE against inappropriate operations.

l Management of NE users

– Five user authority levels are available in an ascending order: monitoring level,operation level, maintenance level, system level, and debugging level.

– Based on network management systems, NE users are classified into LCT NE users,EMS NE users, CMD NE users, and general NE users.

– You can create a user, assign an authority level for the user, and specify the user flag.

– You can change a user name, a password, an authority level, and a user flag.

– You can delete a user.l Management of NE user groups:

– By default, five user groups are available with authorities in an ascending order: monitorgroup, operator group, maintenance personnel group, administrator group, and systemadministrator user group.

– You can query the group to which a user belongs.

9.3 Network Security ManagementThe security of transmitting data between the NMS and NEs, and in networks, is the preconditionfor the NMS to manage the NEs.

Communication between the NMS and NEs can be implemented based on the Access ControlList (ACL), Secure Sockets Layer (SSL), or Remote Authentication Dial-in User Service(RADIUS) protocol.



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ACL Protocol

ACL rules are configured to filter received IP packets. This controls the data traffic on networksand protects against malicious attacks.

You can set basic ACL rules or advanced ACL rules, based on the required system security level.

l For an NE that requires a low security level, you can configure basic ACL rules so that theNE checks only the source addresses of received IP packets.

l For an NE that requires a high security level, you can configure advanced ACL rules. Inthis case, the NE checks the source addresses, sink addresses, source ports, sink ports, andprotocol types of received IP packets.

If both basic and advanced ACL rules are configured, an NE uses only advanced ACL rules tocheck received IP packets.

In addition, ACL rules support the following operations:

l Queries of ACL rules

l Modification of ACL rules

l Deletion of ACL rules

SSL Protocol

The SSL protocol is used to protect the integrity and security of data.

RADIUS Protocol

RADIUS provides a complete network security solution. After a RADIUS server verifies thatthe user name and password of a user are valid, the server allows a certain authority for the user,and provides services to the user.

Carriers' RADIUS servers manage all the user accounts and user attributes of the 550. To log into an OptiX OSN 550 NE, you must apply for a user account to the carrier. When you attemptto log in to an OptiX OSN 550 NE, the RADIUS server verifies the user name and passwordthat you have entered. If the verification fails, a login error is reported.

The OptiX OSN 550 supports the shielding function when being connected to a network portmanagement device. That is, when being connected to a network port on an OptiX OSN 550NE, a network port management device manages only the connected OptiX OSN 550 NE, andcannot access the other devices that are connected to the OptiX OSN 550 NE through ECCs.With this function, even if an OptiX OSN 550 NE in the insecure domain is accessed illegally,the NEs that are connected to the OptiX OSN 550 NE will not be illegally operated.

Security FTP

Security File Transfer Protocol (SFTP) works at the secure shell (SSH) connection layer, andextends support for FTP security based on SSH-provided fundamental services like encryptionand authentication.

l In security, FTP transmits plain text and supports only password authentication, whereasSFTP transmits cipher text and supports both password authentication and cipher keyauthentication. Authentication by cipher key is safer than authentication by password.



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l SFTP needs to perform encryption and decryption and theoretically has a lowertransmission efficiency than FTP. However, benefiting from specialized improvementdesign, SFTP generally has a higher transmission efficiency than FTP.

l SFTP can load packages, upload/download databases, upload log files, and upload/download a single file. NEs can work only as SFTP clients and cannot work as SFTPservers. In addition, SFTP works based on TCP connections and requires IP routes betweenNEs and SSH servers. Therefore, SFTP service can be deployed only at gateway NEs.

9.4 System Security ManagementThe system provides necessary security policies that are executed forcibly.

l Uniqueness of accounts: All accounts held in an NE are unique.

l Complexity of accounts: An account consists of 4 to 16 characters, including letters in lowercase and upper case.

l Length of passwords: A password consists of 8 to 16 characters. To change a password, auser needs to enter the original password once and a new password twice.

l Complexity of passwords:

– A new password consists of at least three of the following character types: lower caseletters, upper case letters, numbers, and special characters.

– A new password must be different from the previous five passwords.

– A new password must be different from an account name, either in the normal writtenformat or in the reversely written format.

– A new password must contain two or more characters different from those of the oldpassword.

l Active period of a password:

– Each password has an active period. After the active period of a password expires, thepassword can be used for only three logins.

– By default, the active period of a password is 0 days, indicating permanent validity.

– For a common user's password, the shortest active period is one day. A common usercan change the password only after the shortest active period expires.

l Storage of passwords: Encrypted passwords are held in the system beyond queries.

l Management of accounts: Accounts can be created, modified, deleted, and queried.

l Query of online users: Users of the administrator group can query other online users.

9.5 Log ManagementThe OptiX OSN 550 supports system security log management and Syslog management.

System Security Log Management

The system security log of an NE records all setting operations and operation results on the NE.By querying the system security log, an administrator can trace and check operations of users.

l You can query the system security log of an NE.



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l You can forward the system security log to the Syslog server.

Syslog Management

The Syslog service is used for the security management of NEs. Different information istransmitted to the Syslog server in a format compliant with the Syslog protocol so thatmaintenance personnel can monitor NEs easily.

The OptiX OSN 550 supports the following functions related to the Syslog protocol:

l Enabling and disabling the Syslog protocol

l Setting the transmission mode of the Syslog protocol to UDP (by default) or TCP or TLS

l Adding or deleting Syslog servers

l Configuration of multiple Syslog servers and transmission of logs to multiple servers at thesame time

l Reporting relevant alarms when the Syslog server fails to communicate with NEs

Figure 9-1 illustrates log transmission on a network by means of the Syslog protocol. To ensurethe security of system logs, at least two Syslog servers are required on a transmission network.NEs communicate with Syslog servers by running the IP protocol. NEs communicate with eachother in many modes, such as HWECC, IP over DCC, and OSI over DCC.

Figure 9-1 Log transmission by means of the Syslog protocol

NMS

Syslog server A

Syslog server BReal-timesecurity log

TCP/IP

NE A(client)

NE B

NE C(client)

NE D

NOTE

A Syslog server is a workstation or server that stores the system logs of all NEs on a network.

Forwarding gateway NEs receive system logs from other NEs, and then forward these system logs to Syslogservers, for example, NE A and NE C in Figure 9-1.

When NEs communicate in IP mode, each NE can directly communicate with two differentSyslog servers by running the IP protocol. Therefore, you need to configure the IP addressesand port numbers of the Syslog servers on an NE. The NE transmits the system log to two Syslogservers by using the automatic routing function of the IP protocol. You do not need to configureany forwarding gateway NE.

When NEs communicate in ECC mode, the NEs that are not directly connected to Syslog serverscannot communicate with Syslog servers. The logs of these NEs need to be transmitted to thegateway NEs that can communicate with Syslog servers directly. Then, the gateway NEs forward



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the logs to Syslog servers. Therefore, you need to configure forwarding gateway NEs. Forexample, you can configure NE A as the forwarding NE of NE D.



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10 Technical Specifications

About This Chapter

This chapter describes general specifications, packet performance indicators, TDM performanceindicators, port specifications, optical module specifications, indicator status explanation, andenvironment indicators of the equipment.

10.1 General SpecificationsThis section lists the chassis dimensions, weight, power consumption, heat consumption, powersupply performance, electromagnetic compatibility, and reliability.

10.2 Packet Performance IndicatorsThis section lists the equipment's packet performance indicators.

10.3 TDM Performance IndicatorsThis section lists the OptiX OSN 550's TDM performance indicators.

10.4 Power Consumption and Weight of Each BoardThis section lists the power consumption and weight of each board that the equipment supports.

10.5 Optical Port SpecificationsThis section lists the specifications of the OptiX OSN 550's STM-1/STM-4/STM-16 opticalports and GE/10GE optical ports.

10.6 Colored Optical PortsThis topic lists the parameters specified for the colored optical ports of the OptiX OSNequipment.

10.7 Electrical Port SpecificationsThis section lists the equipment's electrical port specifications. The equipment's electrical portsinclude PDH electrical ports, CES/ATM/IMA service electrical ports, and Ethernet electricalports.

10.8 Auxiliary Port SpecificationsThis section lists the specifications of auxiliary ports including synchronous data ports,asynchronous data ports, orderwire ports, external clock, and external time ports.

10.9 Indicator Status ExplanationThis section provides status explanation for indicators on boards.

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10.10 Safety CertificationThe OptiX OSN 550 has passed many safety certifications.

10.11 Environmental SpecificationsThe OptiX OSN 550 requires proper environments for storage, transportation, and operation.



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10.1 General SpecificationsThis section lists the chassis dimensions, weight, power consumption, heat consumption, powersupply performance, electromagnetic compatibility, and reliability.

Table 10-1 lists the general specifications of the OptiX OSN 550.

Table 10-1 General specifications of the OptiX OSN 550

Item Description

Dimensions

88 mm x 442 mm x 220 mm (H x W x D)

Weight

3.5 kg (net weight of a chassis that contains one fan board and two PIU boards)

Powerconsumption

l Maximum power consumption: 300 Wl Typical power consumption in Hybrid mode: 149 W

board configuration for typical power consumption: 2 x PCXLX + 3 x EM6F +1 x MD1 + 1 x FAN + 2 x PIU.

SLOT9

(PIU)

SLOT 7 (CST/CSH)

SLOT 1 (EXT )

SLOT 5 (EXT)

SLOT 3 (EXT)

SLOT 2 (EXT )

SLOT 4 (EXT)

SLOT 6 (EXT)

SLOT 8 (CST/CSH)

SLOT10

(PIU)SLO

T11(FAN)

SLOT92

(PIU)

SLOT 7 (PCXLX)

SLOT 1 (EM6F)

SLOT 3 (MD1)

SLOT 2 (EM6F)

SLOT 4 (EM6F)

SLOT91

(PIU) SLOT93

(FAN)

SLOT 8 (PCXLX)

l Typical power consumption in TDM mode: 67 Wboard configuration for typical power consumption: 2×CXL+1×SL1Q+2×SP3D+1×FAN+2×PIU.

SLOT9

(PIU)

SLOT 7 (CST/CSH)

SLOT 5 (EXT)

SLOT 3 (EXT)

SLOT 4 (EXT)

SLOT 6 (EXT)

SLOT 8 (CST/CSH)

SLOT10

(PIU)SLO

T11(FAN)

SLOT92

(PIU)

SLOT 7 (CXL)

SLOT 1 (SL1Q)

SLOT 6 (SP3D)

SLOT 4 (SP3D)

SLOT91

(PIU) SLOT93

(FAN)

SLOT 8 (CXL)

Heatconsumption

l Maximum heat consumption: 1024 BTU/hl Typical heat consumption in Hybrid mode: 508 BTU/hl Typical heat consumption in TDM mode: 229 BTU/h

Powersupplyperformance

l DC power supply

– Rated voltage: -48 V or -60 V

– Voltage range: -38.4 V to -72 Vl AC power supply

– Rated voltage: 110 V or 220 V

– Voltage range: 100 V to 240 V



138

Item Description

Fusecapacity

l DC power supply: 20 Al AC power supply: 5 A

Electromagneticcompatibility

Complies with EMC Class A.

Predictedreliability

l System availability: 0.9999965l Annual average repair rate: < 1.5%l Mean time to repair (MTTR): 1 hourl Mean time between failures (MTBF): 33.08 years

NOTE

In the case of OptiX OSN 550 equipment, power consumption is generally transformed into heatconsumption. Hence, heat consumption (BTU/h) and power consumption (W) can be converted to eachother in the formula: Heat consumption (BTU/h) = Power consumption (W) / 0.2931 (Wh).

10.2 Packet Performance IndicatorsThis section lists the equipment's packet performance indicators.

Table 10-2 lists the OptiX OSN 550's packet performance indicators.

Table 10-2 Packet system performance specifications

Item

Specifications

Protection

MPLS/MPLS-TPtunnelautomaticprotectionswitching(APS)

64NOTE

Tunnel APS, MPLS PW APS, MPLS-TP tunnel APS, and MPLS-TP PW APS shareresources.



139

Item

Specifications

MPLS/MPLS-TPPW APS

Number ofMPLS/MPLS-TP PWAPSprotectiongroups

64NOTE

Tunnel APS, MPLS PW APS, MPLS-TP tunnel APS, and MPLS-TPPW APS share resources.

Number ofboundmembers

512

MRPS Number ofrings

4

Number ofnodesper ring

64

Number ofvirtualnodesperringa

32

Number ofmulticastservices

l Number of multicast services supported by an NE: 16l Number of multicast services supported by a ring: 8

Link-statepassthrough(LPT)

16

Linkaggregation group(LAG)

Number ofLAGs

16



140

Item

Specifications

Number ofmembers in aLAG

8

MultipleSpanningTreeProtocol(MSTP)

Number ofinstancessupported by aport

1

Number of portgroups

1

Number ofportsprovided byportgroups

16

Ethernetringprotectionswitching(ERPS)

8

Linearmultiplexsectionprotection(LMSP) onthe packetplane

8

Maintenance

MPLS/MPLS-TPtunnelOAM

128NOTE

Tunnel OAM, MPLS PW OAM, MPLS-TP tunnel OAM, MPLS-TP PW OAM,ETH OAM, and MRPS OAM (one MRPS ring uses two OAM resources) shareresources.



141

Item

Specifications

MPLS/MPLS-TPPW OAM

128NOTE

Tunnel OAM, MPLS PW OAM, MPLS-TP tunnel OAM, MPLS-TP PW OAM,ETH OAM, and MRPS OAM (one MRPS ring uses two OAM resources) shareresources.

ETH OAM(MPLS/MPLS-TPtunnelOAM,MPLS/MPLS-TPPW OAM,ETHOAM, andMRPSOAMshareresources.)

Number ofmaintenancedomains (MDs)

64

Number ofmaintenanceassociations(MAs)

64

Number ofmaintenanceassociation endpoints(MEPs)

64

Number ofmaintenanceassociationintermediatepoints(MIPs)

64

MRPSOAM

128NOTE

l One MRPS ring uses two OAM resources. MRPS OAM is automatically createdduring the creation of an MRPS ring.

l Tunnel OAM, MPLS PW OAM, MPLS-TP tunnel OAM, MPLS-TP PW OAM,ETH OAM, and MRPS OAM share resources.



142

Item

Specifications

ATMOAM

l Number of local services: 128l Number of remote services: 256

Services

E-Lineservices

1kNOTE

Native ETH services and ETH PWE3 services (VPWSs) share resources.

E-LANservices

Number of E-LANservices(E-LANVSIs)supported by anNE(VSI isshortforvirtualswitchinstance.)

l Native ETH services: 1l ETH PWE3 services (VPLSs): 128NOTE

Native ETH services and ETH PWE3 services (VPLSs) cannot coexiston the same NE.

Number oflogicalportssupported by aVSI

l Native ETH services: 1kl ETH PWE3 services (VPLSs): 128

Number ofvirtualuser-networkinterfaces (V-UNIs)supported by anNE(VPLS)

Number of V-UNIs Number of VLANs

32 4096

64 2047

128 1023

256 511

512 255

1024 127



143

Item

Specifications

Number of splithorizongroupssupported by aVSI

l Native ETH services: 1l ETH PWE3 services (VPLSs): 3

Number oflogicalportssupported by anNE

1k

CESservices

256

ATMservices

Number oflocalservices

128

Number ofremoteservices

256

Multi-LinkPoint-to-PointProtocol(ML-

Number ofML-PPPgroupssupportedby an NE

64

Number ofPPP linkssupportedby an NE

504



144

Item

Specifications

PPP)

Number ofmemberlinkssupportedin an ML-PPP group

16

IGMPsnooping

Number ofmulticastgroups

512

Number ofmembersin amulticastgroup

1K

QoS

Number ofportweightedrandomearlydiscard(WRED)policies

8

Number ofvirtualuser-networkinterface(V-UNI)ingresspolicies

256

Number ofportpolicies

256



145

Item

Specifications

Number ofDifferentiatedServices(DiffServ)domains

8

Number ofport flows

512

Number ofV-UNIingressflows

512

Number oftrafficclassification rules

1

Number ofaccesscontrollists(ACLs)

512

Others

Number ofTunnels

l Unidirectional: 1Kl Bidirectional: 512NOTE

l One bidirectional Tunnel is counted as two unidirectional Tunnels.

l If Tunnels do not carry PWs, the sum of PWs and Tunnels must not exceed 1K.If Tunnels carry PWs, the Tunnels are not counted and the number of carriedPWs must not exceed 1K. Therefore, if each Tunnel carries one PW, the numberof Tunnels and the number of PWs can both be 1K.

l One MPRS ring uses 4 x N tunnels (N is the number of nodes on the MPRSring.) Tunnels are automatically assigned during the configuration of MRPS.

Number ofstatic PWs

1KNOTE

If Tunnels do not carry PWs, the sum of PWs and Tunnels must not exceed 1K. IfTunnels carry PWs, the Tunnels are not counted and the number of carried PWsmust not exceed 1K. Therefore, if each Tunnel carries one PW, the number ofTunnels and the number of PWs can both be 1K.

Number ofMS-PWs

128

Number ofQinQ links

1K



146

Item

Specifications

MACaddresses

Number ofstaticMACaddressessupported by anE-LAN

512

Number ofMACaddressessupported by E-LANservices

16K

Number ofMACaddressessupported by anNE

16K

VLAN IDrangesupportedby a port

1 to 4094

a: MRPS supports protection on intersecting rings. When two rings intersect, one virtualintersecting node can be created to contain the two most remote physical intersecting nodes.If one physical intersecting node fails, services can travel across the rings through the othernode. When a ring intersects with multiple rings, a virtual intersecting node must be createdto contain the two most remote physical intersecting nodes of the ring and each other ring.

10.3 TDM Performance IndicatorsThis section lists the OptiX OSN 550's TDM performance indicators.

Table 10-3 lists the OptiX OSN 550's TDM performance indicators.



147

Table 10-3 OptiX OSN 550 TDM functions and features

Item Description

Service Service Category MaximumReceivingCapability

Service Port


SDH service 26xSTM-1 l S-1.1,L-1.1, andL-1.2opticalports

l STM-1SFPelectricalports

l Opticalport: LC

l Electricalport: SAAstraightfemale


LC


LC

PDH service 252xE1/T1 E1 (75/120-ohm)/T1(100-ohm)electricalports

Anea 96

18xE3/T3 E3 (75-ohm)/T3 (75-ohm)electricalports

SMB



148

Item Description

Ethernet service:l Ethernet private line

(EPL) servicesl Ethernet virtual private

line (EVPL) servicesl Ethernet private LAN

(EPLAN) services(based on the IEEE802.1d bridge)

l Ethernet virtual privateLAN (EVPLAN)services (based on theIEEE 802.1q and802.1ad bridges)

l FE opticalport: 24

l FEelectricalport: 48

l FE opticalport:100BASE-BX,100BASE-FX,100BASE-LX,100BASE-VX, and100BASE-ZX

l FEelectricalport:10/100BASE-T(X)

l Opticalport: LC


24xGE l GE opticalport:1000BASE-SX/LX/VX/ZX

l GEelectricalport:1000BASE-T

l Opticalport: LC


TDMnetwork-levelprotection

SNCP l SNCP at the VC-12, VC-3, and VC-4 levelsl Maximum number of protection groups: 1032


Ring MSP l Ring MSP at the STM-1, STM-4 and STM-16 levelsl Maximum number of protection groups: 13


Linear MSP l Linear MSP at the STM-1, STM-4 and STM-16 levelsl Maximum number of 1+1/1:1 linear MSP protection

groups: 13


Maintenance

PRBS Supported



149

Item Description

Portmirroring

EFS8/EGS4 supports port mirroring that enables Ethernetservice testing and service fault diagnosis without affecting theservices.l Supports local port mirroring.l Supports ingress and egress port mirroring.

Synchronization

Physicallayer clocks

l Including external clocks, line clocks, tributary clocks, andinternal clocks. The port impedance is 120 ohms or 75 ohms(a converter can be used to provide a 75-ohm clock port).

l Non-synchronization status message (SSM), standardSSM, and extended SSM protocols

l Tributary retiming of tributary clocksl Locked mode, holdover mode, and free-run mode

SynchronousEthernet

EGS4 supports synchronous Ethernet clocks.l Synchronous Ethernet clock that complies with ITU-T G.

8261 and ITU-T G.8262.l Port receiving/transmitting synchronous Ethernet clocks:

FE/GEl Clock source selection algorithm based on the

synchronization status message (SSM) protocoll Clock frequency stability (trace mode): < 50 ppbNOTE


10.4 Power Consumption and Weight of Each BoardThis section lists the power consumption and weight of each board that the equipment supports.

Table 10-4 lists the power consumption and weight of each board that the OptiX OSN 550supports.

Table 10-4 Power consumption and weight of each board that the OptiX OSN 550 supports

Board Power Consumption (Roomtemperature (25°C))(W)

Weight (kg)

PCX l PCXLX: 45l PCXX: 44.5l PCXLG: 37l PCXGA/PCXGB: 36.5

0.80

CXL 21 0.50

MD1 12.2 0.50



150

Board Power Consumption (Roomtemperature (25°C))(W)

Weight (kg)

EM6T 10.4 0.37

EM6F 11.3 0.40

EF8F 23 0.55

EG4C l 4xGE optical ports: 12.5l 4xGE electrical ports: 11.0

0.45

EX1 13.1 0.50

CQ1 16 0.50

SL1D 3.5 0.30

SL4D 3.7 0.30

SL1Q 4.5 0.30

SP3D 11.9 0.85

PL3T 4.5 0.30

EFS8 13.0 0.65

EGS4 27.5 0.65

EGT1 8.3 0.60

DMD2 0.5 0.72

AUX 2.2 0.30

PIU 0.5 0.12

APIU 20.0 1.93

FAN 12.0 0.30

10.5 Optical Port SpecificationsThis section lists the specifications of the OptiX OSN 550's STM-1/STM-4/STM-16 opticalports and GE/10GE optical ports.

Specifications of STM-1 Optical PortsTable 10-5 lists the specifications of the OptiX OSN 550's STM-1 optical ports.



151

Table 10-5 Specifications of the two-fiber bidirectional STM-1 optical ports

Item Value

Nominal bit rate 155520 kbit/s

Optical port type S-1.1 L-1.1 L-1.2

Transmission distance(km)

15 40 80

Operating wavelengthrange (nm)

1261 to 1360 1263 to 1360 1480 to 1580

Optical fiber type Single-mode LC Single-mode LC Single-mode LC

Launched optical powerrange (dBm)

-15 to -8 -5 to 0 -5 to 0

Receiver sensitivity(dBm)

-28 -34 -34

Minimum overload(dBm)

-8 -10 -10

Minimum extinction ratio(dB)

8.2 10 10

NOTEFormat of optical port type is defined as follows: transmission distance-signal rate.fiber type

Explanation for optical port type "S-1.1" is as follows: "S" represents short distance; the first digit "1"represents STM-1 signals; the second digit "1" represents ITU-T G.652 fibers (1310 nm).

Explanation for optical port type "L-1.1" is as follows: "L" represents long distance; the first digit "1"represents STM-1 signals; the second digit "1" represents ITU-T G.652 fibers (1310 nm).


Table 10-6 lists the specifications for the single-fiber bidirectional optical interfaces of theOptiX OSN 550's STM-1 optical ports.

Table 10-6 Specifications of the single-fiber bidirectional STM-1 optical ports

Parameter Value


Line code pattern NRZ

Type of optical interface S-1.1 L-1.1


15 40

Type of fiber Single-mode LC Single-mode LC



152

Parameter Value

Operating transmitwavelength (nm)

1550 1310 1550 1310

Operating receivewavelength (nm)

1310 1550 1310 1550


-15 to -8 -5 to 0


-32 -32


-8 -10

Minimum extinctionratio (dB)

8.5 10

Specifications of STM-4 Optical PortsTable 10-7 lists the specifications of the OptiX OSN 550's STM-4 optical ports.


Item Value



Transmissiondistance (km)

15 40 80

Operatingwavelength range(nm)

1274 to 1356 1280 to 1335 1480 to 1580


Launched opticalpower range (dBm)

-15 to -8 -3 to +2 -3 to +2


-28 -28 -28


-8 -8 -8


8.2 10 10



153

Item Value


Explanation for optical port type "S-4.1" is as follows: "S" represents short distance; the first digit "4"represents STM-4 signals; the second digit "1" represents ITU-T G.652 fibers (1310 nm).



Table 10-8 lists the specifications for the single-fiber bidirectional optical interfaces of theOptiX OSN 550's STM-4 optical ports.

Table 10-8 Specifications of the single-fiber bidirectional STM-4 optical ports

Parameter

Value

Nominalbit rate

622080 kbit/s

Line codepattern

NRZ

Type ofopticalinterface

S-4.1 L-4.1

Transmissiondistance(km)

15 40

Type offiber

Single-mode LC Single-mode LC

Operatingtransmitwavelength (nm)

1490 1310 1490 1310

Operatingreceivewavelength (nm)

1310 1490 1310 1490



154

Parameter

Value

Launchedopticalpowerrange(dBm)

-9 to -3 -2 to +3

Receiversensitivity(dBm)

-19.5 -23

Minimumoverload(dBm)

-3 -3

Minimumextinctionratio (dB)

9 9

Specifications of STM-16 Optical Ports

Table 10-9 lists the specifications of the OptiX OSN 550's STM-16 optical ports.


Item Value




15 40 80

Operatingwavelength range(nm)

1260 to 1360 1280 to 1335 1500 to 1580


Launched opticalpower range (dBm)

-5 to 0 -2 to +3 -2 to +3


-18 -27 -28


0 -9 -9


8.2 8.2 8.2



155

Item Value


Explanation for optical port type "S-16.1" is as follows: "S" represents short distance; the first two digits"16" represent STM-16 signals; the third digit "1" represents ITU-T G.652 fibers (1310 nm).

Explanation for optical port type "L-16.1" is as follows: "L" represents long distance; the first two digits"16" represent STM-16 signals; the third digit "1" represents ITU-T G.652 fibers (1310 nm).

Explanation for optical port type "L-16.2" is as follows: "L" represents long distance; the first two digits"16" represent STM-16 signals; the third digit "2" represents ITU-T G.652 fibers (1550 nm).

Specifications of FE Optical PortsTable 10-10 lists the specifications of the OptiX OSN 550's FE optical ports.

Table 10-10 Specifications of the two-fiber bidirectional FE optical ports

Item Value

Optical porttype

100BASE-FX 100BASE-LX 100BASE-VX 100BASE-ZX

Optical fibertype

Multi-mode LC Single-mode LC Single-mode LC Single-mode LC


2 15 40 80

Operatingwavelength(nm)

1270 to 1380 1261 to 1360 1263 to 1360 1480 to 1580

Meanlaunchedpower (dBm)

-19 to -14 -15 to -8 -5 to 0 -5 to 0

Receiverminimumsensitivity(dBm)

-30 -28 -34 -34


-14 -8 -10 -10


10 8.2 10 10



156

Table 10-11 lists the specifications of the OptiX OSN 550's FE single-fiber bidirectional opticalports.

Table 10-11 Specifications of the single-fiber bidirectional FE optical ports

Parameter Value

Type of optical interface 100BASE-BX


15 40

Type of fiber Single-mode LC Single-mode LC

Operating transmitwavelength (nm)

1550 1310 1550 1310

Operating receivewavelength (nm)

1310 1550 1310 1550


-15 to -8 -5 to 0


-32 -32


-8 -10


8.5 10

Specifications of GE Optical PortsTable 10-12 lists the specifications of the OptiX OSN 550's GE optical ports.

Table 10-12 Specifications of the two-fiber bidirectional GE optical ports

Item Value

Optical porttype

1000BASE-SX 1000BASE-LX 1000BASE-VX 1000BASE-ZX

Optical fibertype



0.5 10 40 80


770 to 860 1270 to 1355 1270 to 1355 1500 to 1580



157

Item Value


-9.5 to -2.5 -9 to -3 -5 to 0 -2 to +5


-17 -20 -23 -23


0 -3 -3 -3


9 9 9 9

NOTE

With different SFP modules, the equipment provides GE optical ports with different types and transmissiondistances.

Table 10-13 lists the specifications of the OptiX OSN 550's GE single-fiber bidirectional opticalports.

Table 10-13 Specifications of the single-fiber bidirectional GE optical ports

Parameter

Value

Type ofopticalinterface

1000BASE-LX 1000BASE-VX

Transmissiondistance(km)

10 40

Type offiber


Operatingtransmitwavelength (nm)

1490 1310 1490 1310



158

Parameter

Value

Operatingreceivewavelength (nm)

1310 1490 1310 1490

Launchedopticalpowerrange(dBm)

-9 to -3 -2 to +3


-19.5 -23


-3 -3


9 9

Specifications of 10GE Optical Ports

Table 10-14 lists the specifications of the OptiX OSN 550's 10GE optical ports.

Table 10-14 Specifications of the two-fiber bidirectional 10GE optical ports

Item Value

Optical porttype

10GBASE-SR(LAN)/10GBASE-SW(WAN)

10GBASE-LR(LAN)/10GBASE-LW(WAN)

10GBASE-ER(LAN)/10GBASE-EW(WAN)

10GBASE-ZR(LAN)/10GBASE-ZW(WAN)

Optical fibertype



0.3 10 40 80


840 to 860 1260 to 1355 1530 to 1565 1530 to 1565


-1.3 to -7.3 -8.2 to 0.5 -4.7 to +4 0 to 4



159

Item Value


-7.5 -12.6 -14.1 -21


-1 0.5 -1 -7


3 3.5 3 3

Table 10-15 lists the specifications of the OptiX OSN 550's 10GE single-fiber bidirectionaloptical ports.

Table 10-15 Specifications of the single-fiber bidirectional 10GE optical ports

Item Value

Optical porttype

10GBASE-LR (LAN)/10GBASE-LW (WAN)

10GBASE-ER (LAN)/10GBASE-EW (WAN)

Optical fibertype



10 40

Operatingtransmitwavelength(nm)

1330 1270 1330 1270

Operatingreceivewavelength(nm)

1270 1330 1270 1330


-5 to 0 1 to 5


-14 -15



160

Item Value


0.5 0.5


3.5 3.5

10.6 Colored Optical PortsThis topic lists the parameters specified for the colored optical ports of the OptiX OSNequipment.

GE Optical PortTable 10-16 lists the parameters specified for the colored GE optical ports of the OptiX OSNequipment that comply with ITU-T G.694.1.

Table 10-16 Parameters specified for colored GE optical ports (CWDM)

Parameter Value

CWDM

Nominal bitrate

1,250,000 kbit/s

Type of fiber Single-mode LC


40 80

Launchedoptical powerrange (dBm)

0 to 5 0 to 5

Operatingwavelengthrange (nm)

1471 to 1611, in steps of20

1471 to 1611, in steps of 20


-19 -28

Minimumoverload (dBm)

-3 -9

Minimumextinction ratio(dB)

8.2 8.2



161

10GE Optical Port

Table 10-17 and Table 10-18 list the parameters specified for the colored 10GE optical portsof the OptiX OSN equipment that comply with ITU-T G.694.1.

Table 10-17 Parameters specified for colored 10GE optical ports (CWDM)

Parameter Value

CWDM

Nominal bit rate l LAN mode: 10,312,500 kbit/sl WAN mode: 9,953,280 kbit/s


Transmission distance (km) 70


0 to 4

Operating wavelength range(nm)

1471 to 1611, in steps of 20

Receiver sensitivity (dBm) l 1451 nm to 1551 nm: -23l 1571 nm: -22l 1591 nm to 1611 nm: -21

Minimum overload (dBm) -9


8.2

Table 10-18 Parameters specified for colored 10GE optical ports (DWDM)

Parameter Value

DWDM

Nominal bit rate l LAN mode: 10,312,500 kbit/sl WAN mode: 9,953,280 kbit/s



40 80

Launched opticalpower range(dBm)

-1 to +2 -1 to +3



162

Parameter Value

DWDM

Central frequency(THz)

192.1 to 196.0 192.1 to 196.0

Central frequencydeviation (GHz)

±10 ±10

Receiversensitivity (dBm)

-17 -24


-1 -9


9.5 8.2

STM-1/STM-4/STM-16 Optical Port

Table 10-19 and Table 10-20 list the parameters specified for the colored STM-1/STM-4/STM-16 optical ports of the OptiX OSN equipment that comply with ITU-T G.694.1.

Table 10-19 Parameters specified for colored STM-1/STM-4/STM-16 optical ports (CWDM)

Parameter Value

CWDM

Nominal bitrate

155,520 kbit/s (STM-1), 622,080 kbit/s (STM-4), 2,488,320 kbit/s(STM-16)



40 80

Launchedoptical powerrange (dBm)

0 to 5 0 to 5

Operatingwavelengthrange (nm)

1471 to 1611, in steps of20

1471 to 1611, in steps of 20


-19 -28


-3 -9



163

Parameter Value

CWDM


8.2 8.2

Table 10-20 Parameters specified for colored STM-16 optical ports (DWDM)

Parameter Value

DWDM

Nominal bit rate 2,488,320 kbit/s (STM-16)



120


-1 to +3

Central frequency (THz) 192.1 to 196.0

Central frequencydeviation (GHz)

±10

Receiver sensitivity (dBm) -28

Minimum overload (dBm) -9


8.2

10.7 Electrical Port SpecificationsThis section lists the equipment's electrical port specifications. The equipment's electrical portsinclude PDH electrical ports, CES/ATM/IMA service electrical ports, and Ethernet electricalports.

Specifications of E1/T1 Electrical PortsTable 10-21 lists the specifications of the OptiX OSN 550's E1/T1 electrical ports.



164

Table 10-21 Specifications of E1/T1 electrical ports

Electrical Port Type 1544 kbit/s 2048 kbit/s

Code pattern B8ZS code, AMI code HDB3 code

Waveform at the output port Complies with ITU-T G.703.

Signal bit rate at the output port

Allowed attenuation at the inputport

Permitted frequency deviationat the input port

Complies with ITU-T G.823.

Input jitter tolerance Complies with ITU-T G.824.


Anti-interference capability atthe input port

- Complies with ITU-T G.703.

Reflection attenuation at theinput and output ports

- Complies with ITU-T G.703.

Output jitter Complies with ITU-T G.823 and G.824.

Mapping jitter Complies with ITU-T G.783.

Combined jitter

Jitter transfer function - Complies with ITU-T G.742.

Port type Anea 96

Specifications of E3/T3 Electrical Ports

Table 10-22 lists the specifications of the OptiX OSN 550's E3/T3 electrical ports.

Table 10-22 Specifications of E3/T3 electrical ports

Item Value

Bit rate 34368 kbit/s 44736 kbit/s

Code pattern HDB3 B3ZS

Connector SMB SMB

Port impedance (ohm) 75 75

Signal bit rate at the output port Complies with ITU-T G.703.

Permitted frequency deviation atthe input port



165

Item Value


Input jitter tolerance Complies withITU-T G.823.


Specifications of STM-1 Electrical PortsTable 10-23 lists the specifications of the

OptiX OSN 550's STM-1 electrical ports.

Table 10-23 Specifications of STM-1 electrical ports

Item Value

Bit rate 155520 kbit/s

Code pattern CMI

Connector SAA straight female

Signal bit rate at the output port Complies with ITU-T G.703.

Permitted frequency deviation atthe input port


Input jitter tolerance

Specifications of CES/ATM/IMA Service Electrical Ports

Table 10-24 lists the specifications of the OptiX OSN 550's CES/ATM/IMA service electricalports.

Table 10-24 Specifications of CES/ATM/IMA service electrical ports

Item Value

Standard compliance ITU-T G.703/G.823

Nominal bit rate (kbit/s) 2048

Code pattern HDB3

Impedance (ohm) 75 120

Pair in each direction One coaxial pair One symmetrical pair



166

Item Value

Port type Anea 96

Specifications of Ethernet Electrical PortsTable 10-25 lists the specifications of the OptiX OSN 550's Ethernet electrical ports.

Table 10-25 Specifications of Ethernet electrical ports

Service Port Port Rate Code Pattern Port Type

FE electricalport

10BASE-T Manchester codingsignals

RJ45

FE electricalport

100BASE-T(X) MLT-3 codingsignals

GE electricalport

1000BASE-T 4D-PAM5 codingsignals

10.8 Auxiliary Port SpecificationsThis section lists the specifications of auxiliary ports including synchronous data ports,asynchronous data ports, orderwire ports, external clock, and external time ports.

External Clock Ports

Table 10-26 Specifications of external clock ports

Item Value

External synchronous source 2048 kbit/s (in compliance with ITU-T G.703) or 2048 kHz(in compliance with ITU-T G.703)

Frequency accuracy In compliance with ITU-T G.813

Pull-in or pull-out range

Noise generation

Noise toleration

Noise transfer

Transient response andholdover performance

Synchronization clocktransfer accuracy

< 50 ppb



167

External Time Ports

Table 10-27 Specifications of external time ports

Item Value

Port type l 1PPS+TODl DCLS

Electrical specifications RS-422

Protocol type l 1PPS+TOD: UBX and NMEAl DCLS: IRIG-B (DC)

Synchronous Data Ports

Table 10-28 Specifications of synchronous data ports

Item Value

Transmission channel Byte F1 in the SDH overhead

Bit rate (kbit/s) 64

Port type Codirectional

Port characteristics In compliance with ITU-T G.703

Asynchronous Data Ports

Table 10-29 Specifications of asynchronous data ports

Item Value

Transmission channel User-defined byte in the SDH overhead

Bit rate (kbit/s) ≤ 19.2

Port characteristics In compliance with RS-232



168

Orderwire Ports

Table 10-30 Specifications of orderwire ports

Item Value

Transmission channel Bytes E1 and E2 in the SDH overhead

Orderwire type Addressing call

Pair in each direction One symmetrical pair

Impedance (ohm) 600

Outdoor Cabinet Monitoring Ports

Table 10-31 Specifications of outdoor cabinet monitoring ports

Item Value

Port characteristics In compliance with RS-485

10.9 Indicator Status ExplanationThis section provides status explanation for indicators on boards.

NOTE

There is no indicator on the OptiX OSN 550 chassis.

Table 10-32 provides status explanation for indicators on the boards that the OptiX OSN 550supports.

Table 10-32 Status explanation for indicators on the boards that the OptiX OSN 550 supports

Indicator State Meaning Applicable Board

STAT On (green) The board is workingproperly.

PCX (PCXLX/PCXX/PCXLG/PCXGA/PCXGB)/CXL/MD1/EM6T/EM6F/EF8F/EG4C/EX1/CQ1/SL1D/SL4D/SL1Q/SP3D/PL3T/EFS8/EGS4/EGT1/AUX

On (red) The board hardwareis faulty.

Off l The board is notworking orcreated.

l There is no powersupplied to theboard.



169


PROG Blinks on (green) andoff at 100 msintervals

Software is beingloaded to the boardduring the power-onor resetting processof the board.

PCX (PCXLX/PCXX/PCXLG/PCXGA/PCXGB)/CXL/EM6T/EM6F/EFS8/EGS4

Blinks on (green) andoff at 300 msintervals

The board software isin BIOS boot stateduring the power-onor resetting processof the board.

Blinks on (red) andoff at 100 msintervals

The BOOTROMself-check failsduring the power-onor resetting processof the board.

On (green) l The upper layersoftware is beinginitialized.

l The software isrunning properly.

On (red) l The memory self-check fails orloading upperlayer softwarefails during thepower-on orresetting processof the board.

l The logic file orupper layersoftware is lostduring therunning processof the board.

l The pluggablestorage card isfaulty.

Off The board is notpowered on or worksin low-power mode.

SYNC On (green) The clock is workingproperly.

PCX (PCXLX/PCXX/PCXLG/PCXGA/PCXGB)/CXL



170


On (red) The clock source islost or a clockswitchover occurs.

SRV On (green) The system/service isnormal.

PCX (PCXLX/PCXX/PCXLG/PCXGA/PCXGB)/CXL/MD1/EM6T/EM6F/EF8F/EG4C/EX1/CQ1/SL1D/SL4D/SL1Q/SP3D/PL3T/EFS8/EGS4/EGT1/AUX

On (red) A critical or majoralarm occurs in thesystem/service.

On (yellow) A minor or remotealarm occurs in thesystem/service.

Off l For a PCX board:

– In anunprotectedsystem, thereis no powersupplied to thesystem.

– In a 1+1protectedsystem, theboard worksas the standbyone.

l For a serviceboard, no serviceis configured.

ACT On (green) l In a 1+1 protectedsystem, the boardworks as theactive one.

l In an unprotectedsystem, the boardhas beenactivated.

PCX (PCXLX/PCXX/PCXLG/PCXGA/PCXGB)/CXL/EGT1

Off l In a 1+1 protectedsystem, the boardworks as thestandby one.

l In an unprotectedsystem, the boardis not activated.



171


LINK/LINK1/LINK2

On (green) The GE port isconnected correctly,but is not receiving ortransmitting data.

EM6F/EGT1

Blinks (yellow) The GE port isreceiving ortransmitting data.

Off The GE port is notconnected or isabnormal.

OPM Blinks (red) threetimes every second,300 ms on and 300ms off

The received opticalpower is excessivelyhigh.

EGT1

Blinks (red) onceevery second, 300 mson and 700 ms off

The received opticalpower is excessivelylow.

Blinks (yellow) threetimes every second,300 ms on and 300ms off

The transmittedoptical power isexcessively high.

Blinks (yellow) onceevery second, 300 mson and 700 ms off

The transmittedoptical power isexcessively low.



172


Off Any of the followingstates (including butnot limited to)occurs:l The optical power

is normal.l No optical

module isinstalled.

l An incorrectoptical module isinstalled.

l The E2ROMinformation aboutthe installedoptical modulecannot be readcorrectly.

l The optical fiberis disconnected orthe port isdisabled.

LOS/LOS1/LOS2/LOS3/LOS4

On (red) The optical port onthe board is reportingan R_LOS alarm.

PCX (PCXLX/PCXLG)/SL1D/SL4D/SL1Q/CXL/CQ1

Blinks (red) threetimes every second

The optical port onthe board receivestoo strong power.

Blinks (red) onceevery second

The optical port onthe board receivestoo weak power.

Blinks (red) onceevery three seconds

The optical port onthe board is reportingan MS_RDI alarm.

Off The optical port onthe board is free ofR_LOS alarms.

L/A On (green) The port is connectedcorrectly (link up),but is not receiving ortransmitting data.

PCX (PCXLX/PCXX/PCXLG/PCXGA/PCXGB)/EF8F/EG4C/EX1/EGS4



173


Blinks (red) threetimes every second,300 ms on and 300ms off

The port on the boardreceives too strongpower.

Blinks (red) onceevery second, 300 mson and 700 ms off

The port on the boardreceives too weakpower.

Blinks (orange) The port is connectedcorrectly (link up),and is receiving andtransmitting data.

Off The optical fiber isnot connected to theport, or the port isabnormal (link down/LOS).

PWR On (green) Power is beingsupplied.

PIU

Off Power is off or powersupplies areconnectedincorrectly.

FAN On (green) The FAN board isworking properly.

FAN

On (red) The FAN board isfree of critical/majoralarms.

On (yellow) The FAN board isfree of minor alarms.

Off The FAN board is notpowered on or is notinstalled.

CRIT/MAJ/MIN On (red) The NE has a critical/major alarm.

FAN

On (yellow) The NE has a minoralarm.

Off The NE is free ofcritical/major/minoralarms.



174


INPUT On (green) The voltage of theinput power is withinthe specified range.

APIU

On (red) Undervoltage orovervoltage occurs inthe input power.

OUTPUT On (green) The voltage of theoutput power iswithin the specifiedrange.

APIU

On (red) Undervoltage orovervoltage occurs inthe output power.

ALM On (red) The rectifier moduleis faulty. In normalsituations, theindicator is off.

Rectifier module ofUPM

Vout On (green) The output of therectifier module isnormal.

RUN Flashing (green) The entire powersystem is normal.

Monitoring moduleof UPM

ALM On (red) The entire powersystem is faulty. Innormal situations, theindicator is off.

10.10 Safety CertificationThe OptiX OSN 550 has passed many safety certifications.

Table 10-33 lists the safety certifications that the OptiX OSN 550 has passed.



175

Table 10-33 Safety certifications that the OptiX OSN 550 has passed

Item Standard

Electromagnetic compatibility l CE certificationl ETSI EN 301 489-1l ETSI EN 301 489-4l CISPR 22l EN 55022

Surge protection l ITU-T K.27l ETSI EN 300 253

Safety l CE certificationl ETSI EN 60215l ETSI EN 60950l IEC 60825l GB 4943

Environmental protection l RoHSl REACH

10.11 Environmental SpecificationsThe OptiX OSN 550 requires proper environments for storage, transportation, and operation.

10.11.1 Storage EnvironmentThe storage environment for the OptiX OSN 550 complies with the ETSI EN 300 019-1-1 andNEBS GR-63-CORE standards.

Climate

Table 10-34 lists climate requirements.

Table 10-34 Climate requirements

Item Specification

Atmospheric pressure 70 kPa to 106 kPa

Temperature -40°C to +70°C

Temperature change rate ≤ 1°C/min

Relative humidity 5% to 100%

Solar radiation ≤ 1120 W/m2



176

Item Specification

Heat radiation ≤ 600 W/m2

Waterproofing Requirements

Requirements for storing equipment on site: Generally, the equipment must be stored indoors.

No water should remain on the floor or leak into equipment crates. The equipment should beplaced away from areas where water leakage is possible (for example, do not place nearautomatic fire-fighting extinguishing and heating systems).

Ensure that all the following four conditions are met if the equipment is stored outdoors:

l Crates are intact.

l Proper rain-proofing measures are taken to prevent water from entering crates.

l No water is on the ground where crates are placed and water is not seeped into crates.

l Crates are not exposed to direct sunlight.

Biological Environmentl Avoid multiplication of microbes (such as eumycete and mycete).

l Control and exclude rodents (such as mice).

Air Cleanlinessl The air must be free from explosive, electric-conductive, magnetic-conductive, or corrosive

dust.

l Table 10-35 lists the density requirements for mechanically active substances.

Table 10-35 Density requirements for mechanically active substances

Mechanically Active Substance Content

Suspended dust ≤ 5.00 mg/m3

Precipitable dust ≤ 20.0 mg/(m²·h)

Sand particles ≤ 300 mg/m3

l Table 10-36 lists the density requirements for chemically active substances.

Table 10-36 Density requirements for chemically active substances

Chemically Active Substance Content

SO2 ≤ 0.30 mg/m3



177


H2S ≤ 0.10 mg/m3

NO2 ≤ 0.50 mg/m3

NH3 ≤ 1.00 mg/m3

CL2 ≤ 0.10 mg/m3

HCL ≤ 0.10 mg/m3

HF ≤ 0.01 mg/m3

O3 ≤ 0.05 mg/m3

Mechanical StressTable 10-37 lists requirements for mechanical stress.

Table 10-37 Requirements for mechanical stress

Item Sub-item Specification

Sinusoidalvibration

Displacement 1.5 mm -

Acceleration - 5 m/s2

Frequency range 2 Hz to 9 Hz 9 Hz to 200 Hz

Static load Static pressure Static pressure = Product weight x(Maximum number of stacked layers that isspecified on the product package - 1) x 5 x9.8 (N)

NOTEStatic load is the pressure from the upside that the packaged equipment can tolerate when equipment isstacked in the specified manner.

10.11.2 Transportation EnvironmentThe transportation environment for the OptiX OSN 550 complies with the ETSI EN 300 019-1-2standard.

ClimateTable 10-38 lists climate requirements.



178

Table 10-38 Climate requirements

Item Specification


Temperature -40°C to +70°C

Temperature change rate ≤ 1°C/min

Relative humidity 5% to 95%

Solar radiation ≤ 1120 W/m2

Heat radiation ≤ 600 W/m2

Waterproofing RequirementEnsure that the following conditions are met when transporting the equipment:

l Crates are intact.l Proper rain-proofing measures are taken for vehicles to prevent water from entering crates.l No water is present in vehicles.

Biological Environmentl Avoid multiplication of microbes (such as eumycete and mycete).l Control and exclude rodents (such as mice).

Air Cleanlinessl The air must be free from explosive, electric-conductive, magnetic-conductive, or corrosive

dust.l Table 10-39 lists the density requirements for mechanically active substances.

Table 10-39 Density requirements for mechanically active substances

Mechanically Active Substance Content

Suspended dust No requirement

Precipitable dust ≤ 3.0 mg/(m2·h)

Sand particles ≤ 100 mg/m3

l Table 10-40 lists the density requirements for chemically active substances.



179

Table 10-40 Density requirements for chemically active substances


SO2 ≤ 1.00 mg/m3

H2S ≤ 0.50 mg/m3

NOx ≤ 1.00 mg/m3

NH3 ≤ 3.00 mg/m3

CL2 -

HCL ≤ 0.50 mg/m3

HF ≤ 0.03 mg/m3

O3 ≤ 0.10 mg/m3




Randomvibration

Acceleration spectraldensity

1 m2/s3 -3 dB/oct


Shock Shock responsespectrum I (weight ofsample > 50 kg)

100 m/s2, 11 ms, 100 times for each panel

Shock responsespectrum II (weightof sample ≤ 50 kg)

180 m/s2, 6 ms, 100 times for each panel

Static load Static pressure Static pressure = Product weight x (Maximumnumber of stacked layers that is specified on theproduct package - 1) x 5 x 9.8 (N)

NOTEA shock response spectrum is a graphical representation of an arbitrary transient acceleration input, suchas shock in terms of how the equipment responds to that input.

Static load is the pressure from the upside that the packaged equipment can tolerate when equipment isstacked in the specified manner.



180

10.11.3 Operating Environment (For the Chassis That Is Installed ina Cabinet)

The operating environment for the OptiX OSN 550 complies with the ETSI EN 300 019-1-3class3.2 standard.

ClimateTable 10-42 and Table 10-43 list climate requirements.

Table 10-42 Requirements on temperature and humidity during operation

Operating Temperature Relative Humidity

Long-term operatingtemperature: -5°C to+55°C

Extended operatingtemperature: -5°C to+65°C

Long–term operatingrange: 5% to 85%

Short-term operatingrange: 5% to 95%

NOTEThe temperature and humidity are measured 1.5 m above the floor and 0.4 m ahead of a chassis. Long-term operating indicates that the continuous operating time of the equipment does not exceed 96 hours andthe accumulated annual operating time does not exceed 15 days.

Extended operating indicates that the continuous operating time of the equipment does not exceed 4 hoursper day and the accumulated annual operating time does not exceed 90 days.

To improve equipment reliability, ensure that the equipment room is equipped with a precise airconditioner, which controls temperature and humidity within the following ranges:

l Temperature range: 15°C to 30°Cl Humidity range: 40% to 75%

NOTE

Do not install an air conditioner right above equipment, to prevent air blowing directly from the airconditioner vent into the equipment. Install an air conditioner as far away from a window as possible, toprevent humid air blowing from the window to the equipment.

Table 10-43 Other climate requirements

Item Specification

Altitude -60 m to 4000 m


Temperature change rate 0.5°C/min

Solar radiation ≤ 700 W/m²

Heat radiation ≤ 600 W/m²

Wind speed ≤ 5 m/s



181

NOTE

Between 1800 m and 4000 m of altitude, the equipment operating temperature decreases by 1°C for everyincrease of 220 m in altitude.

Water Resistance and Dust Resistancel If a cabinet is installed indoors or in a corridor that is free from rain, the cabinet must meet

the requirements of IP31 rating protection. (The first numeral "3" indicates that the cabinetcan prevent a solid object with a diameter equal to or greater than 2.5 mm from enteringthe cabinet. The second numeral "1" indicates that vertically falling drops shall have noharmful effects.)

l Ensure that there is no mouse in an equipment room, preventing mouse urine from enteringa cabinet.

Table 10-44 lists the density requirements for mechanically active substances during equipmentoperation.

Table 10-44 Density requirements for mechanically active substances during equipmentoperation

Mechanically ActiveSubstance

Content

Suspended dust ≤0.4 mg/m3

Precipitable dust ≤15 mg/(m2·h)

Sand particles ≤300 mg/m3

Corrosion Protection

Sites must meet the following anti-corrosion requirements:

l Sites must be kept away from pollution sources. If pollution sources cannot be avoided,sites must be located in the perennial upwind direction of the pollution sources, or cabinetsproviding sufficient protection must be used.

– For sources of heavy pollution such as metal smelting plants and coal mines, keep aminimum distance of 5 km.

– For sources of medium pollution such as chemical factories, rubber factories,electroplating factories, agricultural fertilizer factories, paper mills, and power plants,keep a minimum distance of 3.7 km.

– For sources of light pollution such as food factories, leather factories, daily necessitiesfactories, and livestock farms, keep a minimum distance of 2 km.

l Equipment rooms must be kept 3.7 km away from the seaside or salt lakes, and must bekept away from roads or sand fields with dusts flying around. If this requirement cannotbe met, cabinets providing sufficient protection must be used.

l Equipment rooms must be isolated from sewer outlets, sewage treatment tanks, andindustrial/heating boilers, to prevent corrosive gases from eroding components and circuitboards.



182

l Do not install network boxes in underground garages or other garages. If a network boxcan be installed only in a garage, install it at a well-ventilated place and avoid car exhausts,or select a network box providing sufficient protection.

l Power on equipment within seven days after it is installed in a cabinet.

Table 10-45 shows the content limits on corrosive gases.

Table 10-45 Content limits on corrosive gases

Item Content

SO2 ≤ 0.30 mg/m3

H2S ≤ 0.10 mg/m3

NH3 ≤ 1.00 mg/m3

Cl2 ≤ 0.10 mg/m3

HCl ≤ 0.10 mg/m3

HF ≤ 0.01 mg/m3

O3 ≤ 0.05 mg/m3

NOX ≤ 0.50 mg/m3

The requirements for relative humidity at equipment's air intake vents are provided as follows:

NOTE

The relative humidity at equipment's air intake vents must be below 80%. If the relative humidity exceeds80%, the anti-corrosion measures that the equipment provides can only decrease but not eliminate corrosionrisks.

If the humidity control measures that equipment rooms provide cannot keep the relative humidityin the equipment rooms below 80%, adopt appropriate measures listed in Table 10-46.

Table 10-46 Measures for maintaining the relative humidity at equipment's air intake ventsbelow 80%

HeatDissipationMethodThatEquipment Uses

HeatDissipationMethodThatCabinets Use

Suggestion Remarks

Naturaldissipation

Naturaldissipation

None None



183



Suggestion Remarks

Naturaldissipation

Fancooling

Ensure that equipment's air intake vents donot face cabinets' air intake vents, and keep adistance greater than 150 mm between the twotypes of air intake vents, to prevent damp/coldair from entering the equipment.

None

Naturaldissipation

Usingopenracks

Air conditioners and fans must not blowdirectly towards equipment, to prevent damp/cold air from entering the equipment.

None

Fancooling

Naturaldissipation

l Keep a distance greater than 150 mmbetween equipment's air intake vents andcabinets' air intake vents, to prevent damp/cold air from entering equipment.

l Ensure that cabinets have appropriate airintake vents, to prevent a large amount ofdamp/cold air from entering cabinets.

None

Fancooling

Fancooling

l Ensure that equipment's air intake vents donot face cabinets' air intake vents, andkeep a distance greater than 150 mmbetween the two types of air intake vents,to prevent damp/cold air from entering theequipment.

l Ensure that cabinets have appropriate airintake vents, to prevent a large amount ofdamp/cold air from entering cabinets.

l Cabinets must use temperature-controlledfans, to prevent damp/cold air fromentering cabinets. To be specific, fans startat high temperature and stop at lowtemperature. It is recommended that fansstart when the temperature at cabinets' airoutlets exceeds 40°C and stop when thetemperature is lower than 35°C.

When the ambienttemperatureexceeds 30°C, therelative humidityis below 80% inmost areas. Inaddition, thetemperature atcabinets' air outletsis higher than theambienttemperature.Therefore, it isrecommended thatfans stop when thetemperature atcabinets' air outletsis lower than 35°C.



184



Suggestion Remarks

Fancooling

Usingopenracks

l The humidity control measures thatequipment rooms provide must ensure thatthe relative humidity in the equipmentrooms is below 80%; otherwise, corrosionrisks cannot be avoided.

l Air conditioners must not blow cold airdirectly towards equipment, to prevent therelative humidity at equipment's air intakevents from increasing.

l If equipment rooms use air conditioners todecrease temperature, close doorsimmediately after your entrance, toprevent damp air from condensing.

None




Sinusoidalvibration

Velocity ≤ 5 mm/s -

Acceleration - ≤ 2 m/s²


Shock Shock response spectrumII

Half-sine waveform, 30 m/s², 11 ms, 3 ineach direction


10.11.4 Operating Environment (For the Chassis That Is Installedon a Wall)

The operating environment for the OptiX OSN 550 complies with the ETSI EN 300 019-1-3class3.2 standard.



185

Climate

Table 10-48 and Table 10-49 list climate requirements.

Table 10-48 Requirements on temperature and humidity during operation

Operating Temperature Relative Humidity

Long-term operatingtemperature: -5°C to+55°C

Extended operatingtemperature: -5°C to+65°C

Long–term operatingrange: 5% to 85%

Short-term operatingrange: 5% to 95%

NOTEThe temperature and humidity are measured 1.5 m above the floor and 0.4 m ahead of a chassis. Long-term operating indicates that the continuous operating time of the equipment does not exceed 96 hours andthe accumulated annual operating time does not exceed 15 days.

Extended operating indicates that the continuous operating time of the equipment does not exceed 4 hoursper day and the accumulated annual operating time does not exceed 90 days.

To improve equipment reliability, ensure that the equipment room is equipped with a precise airconditioner, which controls temperature and humidity within the following ranges:

l Temperature range: 15°C to 30°C

l Humidity range: 40% to 75%

NOTE

Do not install an air conditioner right above equipment, to prevent air blowing directly from the airconditioner vent into the equipment. Install an air conditioner as far away from a window as possible, toprevent humid air blowing from the window to the equipment.

Table 10-49 Other climate requirements

Item Specification

Altitude -60 m to 4000 m


Temperature change rate 0.5°C/min

Solar radiation ≤ 700 W/m²

Heat radiation ≤ 600 W/m²

Wind speed ≤ 5 m/s

NOTE

Between 1800 m and 4000 m of altitude, the equipment operating temperature decreases by 1°C for everyincrease of 220 m in altitude.



186

Water Resistancel Water resistance requirements for network boxes are provided as follows:

– If a network box is installed indoors or in a corridor that is free from rain, the networkbox must meet the requirements of IP31 rating protection. (The first numeral "3"indicates that the network box can prevent a solid object with a diameter equal to orgreater than 2.5 mm from entering the network box. The second numeral "1" indicatesthat vertically falling drops shall have no harmful effects.)

– If a network box is installed in a corridor that is exposed to rain, the network box mustmeet the requirements of IP55 rating protection. ("IP" indicates international protectionrating. The first numeral "5" indicates the rating for preventing solid objects fromentering network boxes. That is, ingress of dust is not totally prevented, but dust shallnot penetrate in a quantity to interfere with satisfactory operation of equipment or toimpair safety. The second numeral "5" indicates the rating for preventing water fromentering network boxes. That is, water projected in jets against the enclosure from anydirection shall have no harmful effects.)

l Requirements for installing network boxes are provided as follows:

– Equipment must be installed in a position away from water drips (outdoor units andwater pipes of air conditioners, sewer pipes, or windows).

– Equipment must be installed in a position not exposed to rain.

– Equipment must not be installed in light-current wells or directly on the corridor groundon the first floor.

– Equipment must not be mounted on a wall that is near to windows.

– Route cables/fibers into network boxes only from the bottom sides. In addition,waterproof the connection between cables/fibers and network boxes, to prevent rainfrom entering network boxes along cables/fibers.

Dust ResistanceFor dusty areas, network boxes with air filters are recommended (to improve equipmentreliability) and the network boxes must meet the requirements of IP51 rating protection. (Thefirst numeral "5" indicates the rating for preventing solid objects from entering network boxes.That is, ingress of dust is not totally prevented, but dust shall not penetrate in a quantity tointerfere with satisfactory operation of equipment or to impair safety.)

NOTE

For network boxes with air filters, clear the air filters periodically.

Table 10-50 lists the density requirements for mechanically active substances during equipmentoperation.

Table 10-50 Density requirements for mechanically active substances during equipmentoperation


Content

Suspended dust ≤0.4 mg/m3

Precipitable dust ≤15 mg/(m2·h)



187


Content

Sand particles ≤300 mg/m3

Corrosion Protection

Sites must meet the following anti-corrosion requirements:

l Sites must be kept away from pollution sources. If pollution sources cannot be avoided,sites must be located in the perennial upwind direction of the pollution sources, or networkboxes providing sufficient protection must be used.

– For sources of heavy pollution such as metal smelting plants and coal mines, keep aminimum distance of 5 km.

– For sources of medium pollution such as chemical factories, rubber factories,electroplating factories, agricultural fertilizer factories, paper mills, and power plants,keep a minimum distance of 3.7 km.

– For sources of light pollution such as food factories, leather factories, daily necessitiesfactories, and livestock farms, keep a minimum distance of 2 km.

l Installation sites must be kept 3.7 km away from the seaside or salt lakes, and must be keptaway from roads or sand fields with dusts flying around. If this requirement cannot be met,network boxes providing sufficient protection must be used.

l Installation sites must be isolated from sewer outlets, sewage treatment tanks, andindustrial/heating boilers, to prevent corrosive gases from eroding components and circuitboards.

l Do not install network boxes in underground garages or other garages. If a network boxcan be installed only in a garage, install it at a well-ventilated place and avoid car exhausts,or select a network box providing sufficient protection.

l Power on equipment within seven days after it is installed in a network box.

Table 10-51 shows the content limits on corrosive gases.

Table 10-51 Content limits on corrosive gases

Item Content

SO2 ≤ 0.30 mg/m3

H2S ≤ 0.10 mg/m3

NH3 ≤ 1.00 mg/m3

Cl2 ≤ 0.10 mg/m3

HCl ≤ 0.10 mg/m3

HF ≤ 0.01 mg/m3

O3 ≤ 0.05 mg/m3



188

Item Content

NOX ≤ 0.50 mg/m3

The requirements for relative humidity at equipment's air intake vents are provided as follows:

NOTE

The relative humidity at equipment's air intake vents must be below 80%. If the relative humidity exceeds80%, the anti-corrosion measures that the equipment provides can only decrease but not eliminate corrosionrisks.

If the humidity control measures that network boxes provide cannot keep the relative humidityin the network boxes below 80%, adopt appropriate measures listed in Table 10-52.

Table 10-52 Measures for maintaining the relative humidity at equipment's air intake ventsbelow 80%


HeatDissipationMethodThatNetwork BoxesUse

Suggestion Remarks

Naturaldissipation

Naturaldissipation

None None

Naturaldissipation

Fancooling

Ensure that equipment's air intake vents donot face network boxes' air intake vents, andkeep a distance greater than 150 mm betweenthe two types of air intake vents, to preventdamp/cold air from entering the equipment.

None

Fancooling

Naturaldissipation

l Keep a distance greater than 150 mmbetween equipment's air intake vents andnetwork boxes' air intake vents, to preventdamp/cold air from entering equipment.

l Ensure that network boxes haveappropriate air intake vents, to prevent alarge amount of damp/cold air fromentering the network boxes.

None



189


HeatDissipationMethodThatNetwork BoxesUse

Suggestion Remarks

Fancooling

Fancooling

l Ensure that equipment's air intake vents donot face network boxes' air intake vents,and keep a distance greater than 150 mmbetween the two types of air intake vents,to prevent damp/cold air from entering theequipment.

l Ensure that network boxes haveappropriate air intake vents, to prevent alarge amount of damp/cold air fromentering the network boxes.

l Network boxes must use temperature-controlled fans, to prevent damp/cold airfrom entering the network boxes. To bespecific, fans start at high temperature andstop at low temperature. It isrecommended that fans start when thetemperature at network boxes' air outletsexceeds 40°C and stop when thetemperature is lower than 35°C.

When the ambienttemperatureexceeds 30°C, therelative humidityis below 80% inmost areas. Inaddition, thetemperature atnetwork boxes' airoutlets is higherthan the ambienttemperature.Therefore, it isrecommended thatfans stop when thetemperature atnetwork boxes' airoutlets is lowerthan 35°C.




Sinusoidalvibration

Velocity ≤ 5 mm/s -

Acceleration - ≤ 2 m/s²


Shock Shock response spectrumII

Half-sine waveform, 30 m/s², 11 ms, 3 ineach direction




190

11 Energy Saving and EnvironmentalProtection

The OptiX OSN 550 complies with RoHS directive (2002/95/EC), WEEE directive (2002/96/EC) and REACH (REGULATION (EC) No 1907/2006).

Energy SavingThe OptiX OSN 550 adopts a variety of technologies to reduce equipment energy.

l Uses an easy scheme for board design.

l Replaces ordinary chips with ASIC chips that require low power consumption.

l Uses highly efficient power modules.

Environmental Protection

The equipment is designed according to the requirements of environmental protection. Theequipment complies with RoHS/REACH directive.

l The equipment is amply packaged while materials as conserved. The size of the packagecontaining the equipment and accessories is at most three times the size of the netequipment.

l The product is also designed for easy unpacking. All hazardous substances contained inthe packaging decompose easily.

l Every plastic component that weighs over 25 g is labeled according to the standards of ISO11469 and ISO 1043-1 to ISO 1043-4.

l All components and packages of the equipment are provided with standard labels forrecycling.

l Plugs and connectors are easy to find, and the associated operations can be performed byusing simple tools.

l All the attached materials, such as labels, are easy to remove.

l Certain types of identifying information, such as silkscreens, are printed on front panels orsubracks.

OptiX OSN 550 Multi-Service CPE Optical TransmissionSystemProduct Description 11 Energy Saving and Environmental Protection


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12 Standard Compliance

About This Chapter

This section lists the standards that the OptiX OSN 550 complies with.

12.1 ITU-T RecommendationsThis section lists the ITU-T Recommendations that the OptiX OSN equipment complies with.

12.2 IETF StandardsThis section lists the IETF standards that the OptiX OSN equipment complies with.

12.3 IEEE StandardsThis section lists the IEEE standards that the OptiX OSN equipment complies with.

12.4 Environment Related StandardsThis section lists the environment related standards that the OptiX OSN equipment complieswith.

12.5 MEF StandardsThis section lists the MEF standards that the OptiX OSN equipment complies with.

12.6 Safety StandardsThis section lists the safety standards that the OptiX OSN equipment complies with.

12.7 EMC StandardsThis section lists the EMC Standards that the OptiX OSN equipment complies with.

12.8 Protection StandardsThis section lists the protection standards that the OptiX OSN equipment complies with.

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12.1 ITU-T RecommendationsThis section lists the ITU-T Recommendations that the OptiX OSN equipment complies with.

Table 12-1 ITU-T Recommendations

Recommendation

Description

ITU-T G.664 Optical safety procedures and requirements for optical transportsystems

ITU-T G.702 Digital hierarchy bit rates

ITU-T G.703 Physical/electrical characteristics of hierarchical digital interfaces

ITU-T G.704 Synchronous frame structures used at 1544, 6312, 2048, 8448 and44,736 kbit/s hierarchical levels

ITU-T G.706 Frame alignment and cyclic redundancy check (CRC) proceduresrelating to basic frame structures defined in Recommendation G.704

ITU-T G.707 Network node interface for the synchronous digital hierarchy (SDH)

ITU-T G.773 Protocol suites for Q-interfaces for management of transmissionsystems

ITU-T G.774 Synchronous digital hierarchy (SDH) management information modelfor the network element view

ITU-T G.774.1 Synchronous Digital Hierarchy (SDH) performance monitoring for thenetwork element view

ITU-T G.774.2 Synchronous digital hierarchy (SDH) configuration of the payloadstructure for the network element view

ITU-T G.774.3 Synchronous digital hierarchy (SDH) management of multiplex-section protection for the network element view

ITU-T G.774.4 Synchronous digital hierarchy (SDH) management of the sub-networkconnection protection for the network element view

ITU-T G.774.5 Synchronous digital hierarchy (SDH) management of connectionsupervision functionality (HCS/LCS) for the network element view

ITU-T G.774.6 Synchronous digital hierarchy (SDH) unidirectional performancemonitoring for the network element view

ITU-T G.774.7 Synchronous digital hierarchy (SDH) management of lower order pathtrace and interface labeling for the network element view

ITU-T G.774.9 Synchronous digital hierarchy (SDH) configuration of linear multiplexsection protection for the network element view



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Recommendation

Description

ITU-T G.774.10 Synchronous digital hierarchy (SDH) configuration of linear multiplexsection protection for the network element view

ITU-T G.775 Loss of Signal (LOS), Alarm Indication Signal (AIS) and RemoteDefect Indication (RDI) defect detection and clearance criteria for PDHsignals

ITU-T G.7710 Common equipment management function requirements

ITU-T G.780 Vocabulary of terms for synchronous digital hierarchy (SDH) networksand equipment

ITU-T G.781 Synchronization layer functions

ITU-T G.782 Types and Characteristics of Synchronous Digital Hierarchy (SDH)

ITU-T G.783 Characteristics of synchronous digital hierarchy (SDH) equipmentfunctional blocks

ITU-T G.784 Synchronous digital hierarchy (SDH) management

ITU-T G.803 Architecture of transport networks based on the synchronous digitalhierarchy (SDH)

ITU-T G.805 Generic functional architecture of transport networks

ITU-T G.806 Characteristics of transport equipment - Description methodology andgeneric functionality

ITU-T G.808.1 Generic protection switching - Linear trail and sub-network protection

ITU-T G.810 Definitions and terminology for synchronization networks

ITU-T G.811 Timing characteristics of primary reference clocks

ITU-T G.812 Timing requirements of slave clocks suitable for use as node clocks insynchronization networks

ITU-T G.813 Timing characteristics of SDH equipment slave clocks (SEC)

ITU-T G.821 Error performance of an international digital connection operating at abit rate below the primary rate and forming part of an integratedservices digital network

ITU-T G.822 Controlled slip rate objectives on an international digital connection

ITU-T G.823 The control of jitter and wander within digital networks which are basedon the 2048 kbit/s hierarchy

ITU-T G.825 The control of jitter and wander within digital networks which are basedon the synchronous digital hierarchy (SDH)

ITU-T G.826 Error performance parameters and objectives for international,constant bit rate digital paths at or above the primary rate



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Recommendation

Description

ITU-T G.828 Error performance parameters and objectives for international,constant bit rate synchronous digital paths

ITU-T G.829 Error performance events for SDH multiplex and regenerator sections

ITU-T G.831 Management capabilities of transport networks based on thesynchronous digital hierarchy (SDH)

ITU-T G.832 Transport of SDH elements on PDH networks - Frame and multiplexingstructures

ITU-T G.841 Types and characteristics of SDH network protection architectures

ITU-T G.842 Inter-working of SDH network protection architectures

ITU-T G.957 Optical interfaces for equipment and systems relating to thesynchronous digital hierarchy

ITU-T G.958 Digital line systems based on the synchronous digital hierarchy for useon optical fiber cables

ITU-T G.7043/Y.1343

Virtual concatenation of plesiochronous digital hierarchy (PDH)signals

ITU-T G.8010 Architecture of Ethernet layer networks

ITU-T G.8011 Ethernet over Transport - Ethernet services framework

ITU-T G.8011.1 Ethernet private line service

ITU-T G.8011.2 Ethernet virtual private line service

ITU-T G.8012 Ethernet UNI and Ethernet over transport NNI

ITU-T G.8021 Characteristics of Ethernet transport network equipment functionalblocks

ITU-T G.8110 MPLS layer network architecture

ITU-T G.8110.1 Application of MPLS/MPLS-TP in the transport network

ITU-T G.8121 Characteristics of transport MPLS equipment functional blocks

ITU-T G.8112 Interfaces for the transport MPLS (T-MPLS) hierarchy

ITU-T G.8131 Protection switching for transport MPLS (T-MPLS) networks

ITU-T G.8261 Timing and synchronization aspects in packet networks

ITU-T G.8262 Timing characteristics of synchronous Ethernet equipment slave clock(EEC)

ITU-T G.8264 Timing distribution through packet networks

ITU-T Y.1541 Network performance objectives for IP-based services



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Recommendation

Description

ITU-T Y.1710 Requirements for OAM functionality for MPLS networks

ITU-T Y.1730 Requirements for OAM functions in Ethernet based networks andEthernet services

ITU-T Y.1711 Operation & Maintenance mechanism for MPLS networks

ITU-T Y.1720 Protection switching for MPLS networks

ITU-T I.610 B-ISDN operation and maintenance principles and functions

ITU-T Y.1291 An architectural framework for support of quality of service (QoS) inpacket networks

ITU-T G.652 Characteristics of a single-mode optical fiber cable

ITU-T G.655 Characteristics of a non-zero dispersion-shifted single-mode opticalfiber and cable

ITU-T G.671 Transmission characteristics of optical components and subsystems

ITU-T Y.1710 Requirements for OAM functionality for MPLS networks

ITU-T Y.1731 OAM functions and mechanisms for Ethernet based networks

ITU-T G.8032 Ethernet ring protection switching

ITU-T G.8113.1 Operations, administration and maintenance mechanism for MPLS-TPnetworks (G.tpoam)

12.2 IETF StandardsThis section lists the IETF standards that the OptiX OSN equipment complies with.

Table 12-2 IETF standards

Standard Description

RFC 2819 Remote Network Monitoring Management Information Base

draft-ietf-l2vpn-oam-req-frmk-05

L2VPN OAM requirements and framework

RFC 4664 Framework for layer 2 virtual private networks (L2VPNs)

RFC 3031 MPLS architecture

RFC 3469 Framework for multi-protocol label switching (MPLS)-based recovery



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RFC 3811 Definitions of textual conventions for multiprotocol label switching(MPLS) management

RFC 3813 Multiprotocol label switching (MPLS) label switching router (LSR)management information base

RFC 3814 Multiprotocol label switching (MPLS) forwarding equivalence class tonext hop label forwarding entry (FEC-To-NHLFE) managementinformation base

RFC 4115 A differentiated service two-rate, three-color marker with efficienthandling of in-profile traffic

RFC 4221 Multiprotocol label switching (MPLS) management overview

RFC 4377 Operations and management (OAM) requirements for multi-protocollabel switched (MPLS) networks

RFC 4378 A framework for multi-protocol label switching (MPLS) operations andmanagement (OAM)

RFC 3032 MPLS label stack encoding

RFC 3443 Time to live (TTL) processing in multi-protocol label switching (MPLS)networks

RFC 3916 Requirements for pseudo-wire emulation edge-to-edge (PWE3)

RFC 3985 Pseudo wire emulation edge-to-edge (PWE3) architecture

RFC 4197 Requirements for edge-to-edge emulation of time division multiplexed(TDM) circuits over packet switching networks

RFC 4385 Pseudowire emulation edge-to-edge (PWE3) control word for use overan MPLS PSN

RFC 4446 IANA allocations for pseudowire edge to edge emulation (PWE3)

RFC 0826 Ethernet address resolution protocol

RFC 3270 Multi-protocol label switching (MPLS) support of differentiated services

RFC 4448 Encapsulation methods for transport of Ethernet over MPLS networks

RFC 4553 Structure-agnostic time division multiplexing (TDM) over packet(SAToP)

RFC 5085 Pseudo wire virtual circuit connectivity verification (VCCV)

RFC 5086 Structure-Aware Time Division Multiplexed (TDM) Circuit EmulationService over Packet Switched Network (CESoPSN)

RFC 4717 Encapsulation Methods for Transport of Asynchronous Transfer Mode(ATM) over MPLS Networks



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RFC 4816 Pseudowire Emulation Edge-to-Edge (PWE3) Asynchronous TransferMode (ATM) Transparent Cell Transport Service

RFC 4385 Pseudowire emulation edge-to-edge (PWE3) control word for use overan MPLS PSN

RFC 5254 Requirements for Multi-Segment Pseudowire Emulation Edge-to-Edge(PWE3)

draft-ietf-pwe3-segmented-pw-03

Segmented pseudo wire

draft-ietf-pwe3-ms-pw-requirements-03

Requirements for inter domain pseudo-wires

draft-ietf-pwe3-ms-pw-arch-02

An architecture for multi-segment pseudo wire emulation edge-to-edge

RFC 3644 Policy quality of service (QoS) Information model

RFC 2212 Specification of guaranteed quality of service

RFC 2474 Definition of the differentiated services field (DS Field) in the IPv4 andIPv6 headers

RFC 2475 An architecture for differentiated services

RFC 2597 Assured forwarding PHB group

RFC 2698 A two rate three color marker

RFC 3246 An expedited forwarding PHB (Per-hop behavior)

RFC 3270 Multi-protocol label switching (MPLS) support of differentiated services

RFC 5586 MPLS generic associated channel

RFC 5654 Requirements of an MPLS transport profile

RFC 5921 A framework for MPLS in transport networks

RFC 5860 Requirements for operations, administration, and maintenance (OAM) inMPLS transport networks

RFC 1990 The PPP Multilink Protocol (MP)

RFC 5317 Joint Working Team (JWT) Report on MPLS ArchitecturalConsiderations for a Transport Profile

draft-ietf-mpls-tp-oam-analysis

An Overview of the OAM Tool Set for MPLS based Transport Networks

STD 0062 An Architecture for Describing Simple Network Management Protocol(SNMP) Management Frameworks



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12.3 IEEE StandardsThis section lists the IEEE standards that the OptiX OSN equipment complies with.

Table 12-3 IEEE standards


IEEE 802.1D Media Access Control (MAC) Bridges

IEEE 802.1Q Virtual Bridged Local Area Networks

IEEE 802.1ad Virtual Bridged Local Area Networks Amendment 4: Provider Bridges

IEEE 802.3ah Carrier Sense Multiple Access with Collision Detection (CSMA/CD)Access Method and Physical Layer Specifications Amendment: MediaAccess Control Parameters, Physical Layers, and ManagementParameters for Subscriber Access Networks

IEEE 802.1ag Virtual Bridged Local Area Networks - Amendment 5: Connectivity FaultManagement

IEEE 802.3 Carrier Sense Multiple Access with Collision Detection (CSMA/CD)access method and physical layer specifications

IEEE 802.3u Type 100BASE-T MAC parameters, Physical Layer, MAUs, andRepeater for 100 Mb/s Operation

IEEE 802.3x Full Duplex Operation and Type 100BASE-T2

IEEE 802.1w Rapid Reconfiguration of Spanning Tree

IEEE 802.1AX Local and metropolitan area networks - Link Aggregation

IEEE 802.3ad Aggregation of multiple link segments

IEEE 802.3ae Media access control (MAC) parameters, physical Layer, andmanagement parameters for 10 Gb/s operation

IEEE 802.3z Media access control (MAC) parameters, physical Layer, repeater andmanagement parameters for 1000 Mb/s operation

IEEE 802.1ab Link Layer Discovery Protocol

IEEE 802.1p LAN Layer 2 QoS/CoS Protocol for Traffic Prioritization

IEEE 802.1s Multiple Spanning Trees

IEEE 802.3ab Carrier Sense Multiple Access with Collision Detection (CSMA/CD)Access Method and Physical Layer Specifications - Physical LayerParameters and Specifications for 1000 Mb/s Operation over 4 pair ofCategory 5 Balanced Copper Cabling, Type 1000BASE-T



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12.4 Environment Related StandardsThis section lists the environment related standards that the OptiX OSN equipment complieswith.

Table 12-4 Environment related standards


ETSI EN 300019-1-1

Environmental Engineering (EE)Environmental conditions and environmental tests for telecommunica-tions equipmentPart 1-1: Classification of environmental conditions: StorageClass 1.1: Weatherprotected, partly temperature-controlled storagelocationsClass 1.2: Weatherprotected, not temperature-controlled storagelocations

ETSI EN 300019-1-2

Environmental Engineering (EE)Environmental conditions and environmental tests for telecommunica-tions equipmentPart 1-2: Classification of environmental conditions: TransportationClass 2.1: Very careful transportationClass 2.2: Careful transportation

ETSI EN 300019-1-3

Environmental Engineering (EE)Environmental conditions and environmental tests for telecommunica-tions equipmentPart 1-3: Classification of environmental conditions: Stationary use atweatherprotected locationsClass 3.1: Temperature-controlled locationsClass 3.2: Partly temperature-controlled location

IEC 60068-2 Basic environmental testing procedures

IEC 60721-2-6 Environmental conditions appearing in nature - Earthquake vibration

IEC 60721-3-1 Classification of environmental conditions - Part 3: Classification ofgroups of environmental parameters and their severities - Section 1:Storage

IEC 60721-3-3 Classification of environmental conditions - Part 3: Classification ofgroups of environmental parameters and their severities - Section 3:Stationary use at weatherprotected locations

ETSI EN 300 753 Equipment Engineering (EE)Acoustic noise emitted by telecommunications equipment



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NEBS GR-63-CORE

Network Equipment-Building System (NEBS) Requirements: PhysicalProtection

ROHS Restriction of the use of certain hazardous substance in electrical andelectronic equipment.

ETSI EN 300019-2-3

Equipment Engineering (EE); Environmental conditions andenvironmental tests for telecommunications equipmentPart 2-3: Specification of environmental tests Stationary use atweatherprotected locations

12.5 MEF StandardsThis section lists the MEF standards that the OptiX OSN equipment complies with.

Table 12-5 MEF standards


MEF 2 Requirements and framework for Ethernet service protection in metroEthernet networks

MEF 4 Metro Ethernet network architecture framework - Part 1: generic framework

MEF 9 Abstract Test Suite for Ethernet Services at the UNI

MEF 10 Ethernet services attributes phase 1

MEF 14 Abstract Test Suite for Traffic Management Phase 1

12.6 Safety StandardsThis section lists the safety standards that the OptiX OSN equipment complies with.

Table 12-6 Safety standards

Safety Standard Description

EN 60950-1 Safety of information technology equipment

EN 60825-1 Safety of laser products - Part 1: Equipment classification andrequirements

EN 60825-2 Safety of laser products - Part 2: Safety of optical fibrecommunication systems

IEC 60950-1 Safety of information technology equipment



201

Safety Standard Description

IEC 60825-1 Safety of laser equipment

IEC 60825-2 Safety of laser equipment - requirement of OFCS

EN 60950 Information technology equipment - safety

IEC 60950 Safety of information technology equipment includingelectrical business equipment

CAN/CSA-C22.2 No 1-M94

Audio, video and similar electronic equipment

CAN/CSA-C22.2 No950-95

Safety of information technology equipment

73/23/EEC 2006/95/EC

UL60950-1 Safety of information technology equipment

IEC 60529 Degrees of protection provided by enclosures (IP Code)

GR-1089-CORE Electromagnetic Compatibility and Electrical Safety

EG 201 212 Electrical safety; Classification of interfaces for equipment tobe connected to telecommunication networks

ITU-T G.644 Optical safety procedures and requirements for optical transportsystems

EN 41003IEC 41003

Particular safety requirements for equipment to be connected totelecommunications networks and/or a cable distributionsystem

12.7 EMC StandardsThis section lists the EMC Standards that the OptiX OSN equipment complies with.

Table 12-7 EMC related standards


EN 61000-3-2 Electromagnetic compatibility (EMC) – Part 3-2: Limits – Limitsemissions (equipment input current up to and including 16 A perphase) – (IEC 61000-for harmonic current 3-2:2005 + A1:2008 +A2:2009)

EN 61000-3-11 Electromagnetic compatibility (EMC) – Part 3-11: Limits –voltage fluctuations and flicker in public low-voltage supplysystems – EquipmentLimitation of voltage changes,with ratedcurrent <= 75 A and subject to conditional connection



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IEC 61000-4-2EN 61000-4-2

Electromagnetic compatibility-Part4-2: Testing and measurementtechniques-Electrostatic discharge immunity test

IEC 61000-4-3EN 61000-4-3

Electromagnetic compatibility (EMC)-Part 4-3: Testing andmeasurement techniques-Radiated, radio-frequency,electromagnetic field immunity test

IEC 61000-4-4EN 61000-4-4

Electromagnetic compatibility (EMC)-Part 4-4: Testing andmeasurement techniques-Electrical fast transient/burst immunitytest

IEC 61000-4-5EN 61000-4-5

Electromagnetic compatibility (EMC)-Part 4-5: Testing andmeasurement techniques-Surge immunity test

IEC 61000-4-6EN 61000-4-6

Electromagnetic compatibility (EMC)-Part 4-6: Testing andmeasurement techniques-Immunity to conducted disturbances,induced by radio-frequency fields

IEC 61000-4-29EN 61000-4-29

Electromagnetic compatibility (EMC)-Part 4-29: Testing andmeasurement techniques-Voltage dips, shot interruptions andvoltage variations on d.c. input power port immunity tests

CISPR 22/EN 55022 Information technology equipment-Radio disturbancecharacteristics-Limits and methods of measurement

CISPR 24/EN 55024 Information technology equipment-immunity characteristics-Limits and methods of measurement

ETSI EN 300386 Electromagnetic compatibility and Radio Spectrum Matters(ERM); Telecommunication network equipment;ElectroMagnetic Compatibility (EMC) requirements

ETSI EN 201468 Electromagnetic compatibility and Radio spectrum Matters(ERM); Additional ElectroMagnetic Compatibility (EMC)telecommunications equipment for enhanced availability ofservice in specific applications

ETSI EN 300127 Electromagnetic compatibility and Radio spectrum Matters(ERM); Radiated emission testing of physically largetelecommunication systems

ETSI EN 300132-2 Power supply interface at the input to telecommunicationsequipment; Part 2: Operated by direct current (dc)

EN 50121-4 Railway applications-Electromagnetic Compatibility-Part 4:Emission and immunity of the signalling and telecommunicationsapparatus



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12.8 Protection StandardsThis section lists the protection standards that the OptiX OSN equipment complies with.

Table 12-8 Protection related standards


IEC 61024-1 Protection of structures against lightning

IEC 61312-1 Protection against lightning electromagnetic impulse part I: generalprinciples

IEC 61000-4-5 Electromagnetic compatibility (EMC) Part 4: Testing and measurementtechniques Section 5: Surge immunity test

ITU-T K.11 Principles of protection against overvoltage and overcurrents

ITU-T K.20 Resistibility of telecommunication switching equipment to overvoltagesand overcurrents

ITU-T K.27 Bonding configurations and earthing inside a telecommunicationbuilding

ITU-T K.41 Resistibility of internal interfaces of telecommunication centers to surgeovervoltages



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A Glossary

Numerics

1+1 backup A backup method in which two components mirror each other. If the active componentgoes down, the standby component takes over services from the active component toensure that the system service is not interrupted.

1:N protection An architecture that has N normal service signals, N working SNCs/trails, and oneprotection SNC/trail. It may have one extra service signal.

3G See 3rd Generation.

3R reshaping, retiming, regenerating

3rd Generation (3G) The third generation of digital wireless technology, as defined by the InternationalTelecommunications Union (ITU). Third generation technology is expected to deliverdata transmission speeds between 144 kbit/s and 2 Mbit/s, compared to the 9.6 kbit/s to19.2 kbit/s offered by second generation technology.

A

A/D analog/digit

AAA See Authentication, Authorization and Accounting.

AAL See ATM Adaptation Layer.

AAL2 ATM Adaptation Layer Type 2

AAL5 ATM Adaptation Layer Type 5

ABR See available bit rate.

ACAP See adjacent channel alternate polarization.

ACH associated channel header

ACL See access control list.

ACL rule A rule for controlling the access of users.

ADM add/drop multiplexer

AF See assured forwarding.

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205

AGC automatic gain control

AIO asynchronous input/output

AIS alarm indication signal

AIS insertion Insertion of AIS in a channel with excessive errors to indicate that it is unavailable. Fora line board, it can be set whether to insert AIS when there are excessive errors in theB1, B2 and B3 bytes. For tributary board at the E1/T1 level, it can be set whether toinsert AIS when there are excessive errors in BIP-2. For tributary board at the E3 levelor higher, it can be set whether to insert AIS when there are excessive errors in the B3byte.

ALS See automatic laser shutdown.

AM See adaptive modulation.

AMI See alternate mark inversion.

ANSI See American National Standards Institute.

APD See avalanche photodiode.

APID access point identifier

APS automatic protection switching

APS 1+1 protection A protection architecture that comprises one protection facility and one working facilityand performs switchover by using the Automatic Protection Switching (APS) protocol.Normally, signals are sent only over the working facility. If an APS switchover event isdetected by the working facility, services are switched over to the protection facility.

ARP See Address Resolution Protocol.

AS See autonomous system.

ASCII American Standard Code for Information Interchange

ASK amplitude shift keying

ATM asynchronous transfer mode

ATM AdaptationLayer (AAL)

An interface between higher-layer protocols and Asynchronous Transfer Mode (ATM).The AAL provides a conversion function to and from ATM for various types ofinformation, including voice, video, and data.

ATM protection group Logically bound ATM VP network/subnetwork connections that share the same physicaltransmission channel. In the VP Group (VPG), a pair of VP connections (workingconnection and its protective connection) is used for monitoring the automatic protectionswitching, called monitoring connections (APS VPCs). If the monitoring connectionsswitch over, the whole VPG will switch over to quicken the ATM protection switching(as quick as the protection switching of the SDH layer).

ATPC See automatic transmit power control.

AU See administrative unit.

AUG See administrative unit group.

AWG arrayed waveguide grating



206

Address ResolutionProtocol (ARP)

An Internet Protocol used to map IP addresses to MAC addresses. The ARP protocolenables hosts and routers to determine link layer addresses through ARP requests andresponses. The address resolution is a process by which the host converts the target IPaddress into a target MAC address before transmitting a frame. The basic function ofARP is to use the target equipment's IP address to query its MAC address.

American NationalStandards Institute(ANSI)

An organization that defines U.S standards for the information processing industry.

Authentication,Authorization andAccounting (AAA)

A mechanism for configuring authentication, authorization, and accounting securityservices. Authentication refers to the verification of user identities and the relatednetwork services; authorization refers to the granting of network services to usersaccording to authentication results; and accounting refers to the tracking of theconsumption of network services by users.

access A link between the customer and the telecommunication network. Many technologies,such as the copper wire, optical fiber, mobile, microwave and satellite, are used foraccess.

access control list(ACL)

A list of entities, together with their access rights, which are authorized to access aresource.

access layer A layer that connects the end users (or last mile) to the ISP network. The access layerdevices are cost-effective and have high-density interfaces. In an actual network, theaccess layer includes the devices and cables between the access points and the UPEs.

access point Any entity that has station functionality and provides access to the distribution services,via the wireless medium (WM) for associated stations.

accumulation The sum of the service usage, consumption, and recharge fees of a subscriber.

active link A link in the link aggregation group, which is connected to the active interface.

active mode A working mode of EFM OAM. The discovery and remote loopback can only be initiatedby the interface in the active mode.

adaptive modulation(AM)

A technology that is used to automatically adjust the modulation mode according to thechannel quality. When the channel quality is favorable, the equipment uses a high-efficiency modulation mode to improve the transmission efficiency and the spectrumutilization of the system. When the channel quality is degraded, the equipment uses thelow-efficiency modulation mode to improve the anti-interference capability of the linkthat carries high-priority services.

adjacency A portion of the local routing information which pertains to the reachability of a singleneighbor ES or IS over a single circuit. Adjacencies are used as input to the DecisionProcess for forming paths through the routing domain. A separate adjacency is createdfor each neighbor on a circuit, and for each level of routing (i.e. level 1 and level 2) ona broadcast circuit.

adjacent channelalternate polarization(ACAP)

A channel configuration method, which uses two adjacent channels (a horizontalpolarization wave and a vertical polarization wave) to transmit two signals.

adjacent concatenation A situation where the virtual containers (VC) to carry concatenated services in SDH areconsecutive in terms of their service in the frame structures, so that they use the samepath overhead (POH).



207

administrative unit(AU)

The information structure that enables adaptation between the higher order path layerand the multiplex section layer. The administrative unit consists of an informationpayload (the higher order VC) and an AU pointer, which indicates the offset of thepayload frame start relative to the multiplex section frame start.

administrative unitgroup (AUG)

One or more administrative units occupying fixed, defined positions in an STM payload.An AUG consists of AU-4s.

advanced ACL An ACL that defines ACL rules based on the source addresses, target addresses, protocoltype, such as TCP source or target port, the type of the ICMP protocol, and messagecodes.

aggregated link Multiple signaling link sets between two nodes.

aging time The time to live before an object becomes invalid.

air interface The interface between the cellular phone set or wireless modem (usually portable ormobile) and the active base station.

alarm A message reported when a fault is detected by a device or by the network managementsystem during the device polling process. Each alarm corresponds to a clear alarm. Aftera clear alarm is received, the corresponding alarm is cleared.

alarm box A device that reflects the status of an alarm in visual-audio mode. The alarm box notifiesyou of the alarm generation and alarm severity after it is connected to the SignalingNetwork Manager server or client and the related parameters are set.

alarm cascading The method of cascading alarm signals from several subracks or cabinets.

alarm correlationanalysis

A process to analyze correlated alarms. For example, if alarm 2 is generated within fiveseconds after alarm 1 is generated, and it complies with the conditions defined in thealarm correlation analysis rule, you can either mask the alarm or raise the level of alarm2 according to the behavior defined in the alarm correlation rule.

alarm filtering An alarm management method. Alarms are detected and reported to the NMS system,and whether the alarm information is displayed and saved is decided by the alarm filteringstatus. An alarm with the filtering status set to "Filter" is not displayed and saved on theNMS, but is monitored on the NE.

alarm indication A mechanism to indicate the alarm status of equipment. On the cabinet of an NE, fourdifferently-colored indicators specify the current status of the NE. When the greenindicator is on, the NE is powered on. When the red indicator is on, a critical alarm hasbeen generated. When the orange indicator is on, a major alarm has been generated.When the yellow indicator is on, a minor alarm has been generated. The ALM alarmindicator on the front panel of a board indicates the current status of the board.

alarm inversion mode A mode for an NE that indicates whether the port is automatically restored to the normalstatus after the service is accessed or the fault is removed. There are three alarm inversionmodes: normal, revertible and non-revertible.

alarm notification When an error occurs, the performance measurement system sends performance alarmsto the destination (for example, a file and/or fault management system) designated byusers.

alarm suppression A method to suppress alarms for the alarm management purpose. Alarms that aresuppressed are no longer reported from NEs.

alternate markinversion (AMI)

A synchronous clock encoding technique which uses bipolar pulses to represent logical1 values.



208

analog signal A signal in which information is represented with a continuously variable physicalquantity, such as voltage. Because of this constant changing of the wave shape withregard to its passing a given point in time or space, an analog signal might have a virtuallyindefinite number of states or values. This contrasts with a digital signal that is expressedas a square wave and therefore has a very limited number of discrete states. Analogsignals, with complicated structures and narrow bandwidth, are vulnerable to externalinterference.

assured forwarding(AF)

One of the four per-hop behaviors (PHB) defined by the Diff-Serv workgroup of IETF.It is suitable for certain key data services that require assured bandwidth and short delay.For traffic within the bandwidth limit, AF assures quality in forwarding. For traffic thatexceeds the bandwidth limit, AF degrades the service class and continues to forward thetraffic instead of discarding the packets.

attack An attempt to bypass security controls in a system with the mission of using that systemor compromising it. An attack is usually accomplished by exploiting a currentvulnerability.

attenuation Reduction of signal magnitude or signal loss, usually expressed in decibels.

attenuator A device used to increase the attenuation of an Optical Fiber Link. Generally used toensure that the signal at the receive end is not too strong.

automatic lasershutdown (ALS)

A technique (procedure) to automatically shutdown the output power of laser transmittersand optical amplifiers to avoid exposure to hazardous levels.

automatic transmitpower control (ATPC)

A method of adjusting the transmit power based on fading of the transmit signal detectedat the receiver

autonomous system(AS)

A network set that uses the same routing policy and is managed by the same technologyadministration department. Each AS has a unique identifier that is an integer rangingfrom 1 to 65535. The identifier is assigned by IANA. An AS can be divided into areas.

availability A capability of providing services at any time. The probability of this capability is calledavailability.

available bit rate (ABR) A kind of service categories defined by the ATM forum. ABR only provides possibleforwarding service and applies to the connections that does not require the real-timequality. It does not provide any guarantee in terms of cell loss or delay.

avalanche photodiode(APD)

A semiconductor photodetector with integral detection and amplification stages.Electrons generated at a p/n junction are accelerated in a region where they free anavalanche of other electrons. APDs can detect faint signals but require higher voltagesthan other semiconductor electronics.

average delay A performance indicator indicating the average RTT of multiple ping operations or otherprobe operations. It is expressed in milliseconds.

B

B-ISDN See broadband integrated services digital network.

BA booster amplifier

BBE background block error

BC boundary clock

BCD binary coded decimal



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BDI See backward defect indication.

BDI packet A packet used to notify the upstream LSR of the failure event which has occurred on thedownstream LSR through the reverse LSP. The BDI packet can be used in the 1:1/Nprotective switchover service.

BE See best effort.

BER bit error rate

BFD See Bidirectional Forwarding Detection.

BGP Border Gateway Protocol

BIP See bit interleaved parity.

BIP-8 See bit interleaved parity-8.

BIP-X bit interleaved parity-X

BITS See building integrated timing supply.

BMC best master clock

BNC See bayonet-neill-concelman.

BOM bill of materials

BPDU See bridge protocol data unit.

BPS board protection switching

BSC See base station controller.

BSS base station subsystem

BTS base transceiver station

BW See bandwidth.

BWS backbone wavelength division multiplexing system

BidirectionalForwarding Detection(BFD)

A fast and independent hello protocol that delivers millisecond-level link failuredetection and provides carrier-class availability. After sessions are established betweenneighboring systems, the systems can periodically send BFD packets to each other. Ifone system fails to receive a BFD packet within the negotiated period, the system regardsthat the bidirectional link fails and instructs the upper layer protocol to take actions torecover the faulty link.

backbone network A network that forms the central interconnection for a connected network. Thecommunication backbone for a country is WAN. The backbone network is an importantarchitectural element for building enterprise networks. It provides a path for the exchangeof information between different LANs or subnetworks. A backbone can tie togetherdiverse networks in the same building, in different buildings in a campus environment,or over wide areas. Generally, the backbone network's capacity is greater than thenetworks connected to it.

backplane An electronic circuit board containing circuits and sockets into which additionalelectronic devices on other circuit boards or cards can be plugged.

backup A periodic operation performed on data stored in a database for the purposes ofrecovering the data if an error occurs. The backup also refers to the data synchronizationbetween active and standby boards.



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backward defectindication (BDI)

A function that the sink node of a LSP, when detecting a defect, uses to inform theupstream end of the LSP of a downstream defect along the return path.

bandwidth (BW) A range of transmission frequencies a transmission line or channel can carry in a network.In fact, the bandwidth is the difference between the highest and lowest frequencies inthe transmission line or channel. The greater the bandwidth, the faster the data transferrate.

base station area An area of radio coverage consisting of cells served by one or more Base TransceiverStations (BTSs) in the same base station site.

base station controller(BSC)

A logical entity that connects the BTS with the MSC in a GSM/CDMA network. Itinterworks with the BTS through the Abis interface, the MSC through the A interface.It provides the following functions: radio resource management, base stationmanagement, power control, handover control, and traffic measurement. One BSCcontrols and manages one or more BTSs in an actual network.

baseband A form of modulation in which the information is applied directly onto the physicaltransmission medium.

bayonet-neill-concelman (BNC)

A connector used for connecting two coaxial cables.

bearer An information transmission path with defined capacity, delay and bit error rate.

bearer network A network used to carry the messages of a transport-layer protocol between physicaldevices.

best effort (BE) A traditional IP packet transport service. In this service, the diagrams are forwardedfollowing the sequence of the time they reach. All diagrams share the bandwidth of thenetwork and routers. The amount of resource that a diagram can use depends of the timeit reaches. BE service does not ensure any improvement in delay time, jitter, packet lossratio, and high reliability.

best-effort service A unitary and simple service model. Without being approved, but after notifying thenetwork, the application can send any number of packets at any time. The network triesits best to send the packets, but delay and reliability cannot be ensured. Best-Effort isthe default service model of the Internet. It can be applied to various networks, such asFTP and E-Mail. It is implemented through the First In First-Out (FIFO) queue.

bit error An incompatibility between a bit in a transmitted digital signal and the correspondingbit in the received digital signal.

bit interleaved parity(BIP)

A method of error monitoring. With even parity, the transmitting equipment generatesan X-bit code over a specified portion of the signal in such a manner that the first bit ofthe code provides even parity over the first bit of all X-bit sequences in the coveredportion of the signal, the second bit provides even parity over the second bit of all X-bitsequences within the specified portion, and so forth. Even parity is generated by settingthe BIP-X bits so that an even number of 1s exist in each monitored partition of thesignal. A monitored partition comprises all bits in the same bit position within the X-bitsequences in the covered portion of the signal. The covered portion includes the BIP-X.

bit interleaved parity-8(BIP-8)

Consists of a parity byte calculated bit-wise across a large number of bytes in atransmission transport frame. Divide a frame is into several blocks with 8 bits (one byte)in a parity unit and then arrange the blocks in matrix. Compute the number of "1" or "0"over each column. Then fill a 1 in the corresponding bit for the result if the number isodd, otherwise fill a 0.



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blacklist A method of filtering packets based on their source IP addresses. Compared with ACL,the match condition for the black list is much simpler. Therefore, the black list can filterpackets at a higher speed and can effectively screen the packet sent from the specific IPaddress.

bound path A parallel path with several serial paths bundled together. It improves the data throughputcapacity.

bridge A device that connects two or more networks and forwards packets among them. Bridgesoperate at the physical network level. Bridges differ from repeaters because bridges storeand forward complete packets, while repeaters forward all electrical signals. Bridgesdiffer from routers because bridges use physical addresses, while routers use IPaddresses.

bridge protocol dataunit (BPDU)

Data messages exchanged across switches within an extended LAN that uses a spanningtree protocol (STP) topology. BPDU packets contain information on ports, addresses,priorities, and costs, and they ensure that the data reaches its intended destination. BPDUmessages are exchanged across bridges to detect loops in a network topology. Theseloops are then removed by shutting down selected bridge interfaces and placingredundant switch ports in a backup, or blocked, state.

bridging The act of simultaneously transmitting identical traffic on the working and protectionchannels.

broadband integratedservices digital network(B-ISDN)

A standard defined by the ITU-T to handle high-bandwidth applications, such as voice.It currently uses the ATM technology to transmit data over SONNET-based circuits at155 to 622 Mbit/s or higher speed.

broadcast A means of delivering information to all members in a network. The broadcast range isdetermined by the broadcast address.

broadcast address A network address in computer networking that allows information to be sent to all nodeson a network, rather than to a specific network host.

broadcast domain A group of network stations that receives broadcast packets originating from any devicewithin the group. The broadcast domain also refers to the set of ports between which adevice forwards a multicast, broadcast, or unknown destination frame.

building integratedtiming supply (BITS)

In the situation of multiple synchronous nodes or communication devices, one can usea device to set up a clock system on the hinge of telecom network to connect thesynchronous network as a whole, and provide satisfactory synchronous base signals tothe building integrated device. This device is called BITS.

built-in WDM A function which integrates some simple WDM systems into products that belong to theOSN series. That is, the OSN products can add or drop several wavelengths directly.

burst A process of forming data into a block of the proper size, uninterruptedly sending theblock in a fast operation, waiting for a long time, and preparing for the next fast sending.

C

CAC See connection admission control.

CAR committed access rate



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CAS multiframe A multiframe set up based on timeslot 16. Each CAS multiframe contains 16 E1 PCMframes. Among the 8 bits of timeslot 16 in the first frame, the first 4 bits are used formultiframe synchronization. The multiframe alignment signal (MFAS) forsynchronization is 0000. The last 4 bits are used as the not multiframe alignment signal(NMFAS). The NMFAS is XYXX. For the other 15 frames, timeslot 16 is used totransmit exchange and multiplexing (E&M) signaling corresponding to each timeslot.

CBR See constant bit rate.

CBS See committed burst size.

CC See continuity check.

CCDP See co-channel dual polarization.

CCS See Common Channel Signaling.

CDVT cell delay variation tolerance

CE See customer edge.

CES See circuit emulation service.

CFM connectivity fault management

CFR cell fill rate

CIR committed information rate

CIST See Common and Internal Spanning Tree.

CLEI common language equipment identification

CLK clock card

CLNP connectionless network protocol

CLP See cell loss priority.

CMI coded mark inversion

CO central office

CPU See central processing unit.

CR connection request

CRC See cyclic redundancy check.

CRC-4 multiframe A multiframe recommended by ITU-T G.704 and set up based on the first bit of timeslot0. The CRC-4 multiframe is different from the CAS multiframe in principle andimplementation. Each CRC-4 multiframe contains 16 PCM frames. Each CRC-4multiframe consists of two CRC-4 sub-multiframes. Each CRC-4 sub-multiframe is aCRC-4 check block that contains 2048 (256 x 8) bits. Bits C1 to C4 of a check block cancheck the previous check block.

CSA Canadian Standards Association

CSES consecutive severely errored second

CSF Client Signal Fail

CSMA/CD See carrier sense multiple access with collision detection.

CST See common spanning tree.



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CTC common transmit clock

CV connectivity verification

CV packet A type of packet that is generated at the frequency of 1/s on the source end LSR of anLSP, and is terminated on the destination end LSR of the LSP. A CV packet is transmittedfrom the source end LSR to the destination LSR along the LSP. A CV packet containsthe unique identifier (TTSI) of the LSP so that all types of abnormalities on the path canbe detected.

CW control word

CWDM See coarse wavelength division multiplexing.

Common ChannelSignaling (CCS)

A signaling system used in telephone networks that separates signaling information fromuser data. A specified channel is exclusively designated to carry signaling informationfor all other channels in the system.

Common and InternalSpanning Tree (CIST)

The single spanning tree jointly calculated by STP and RSTP, the logical connectivityusing MST bridges and regions, and MSTP. The CIST ensures that all LANs in thebridged local area network are simply and fully connected.

cabinet Free-standing and self-supporting enclosure for housing electrical and/or electronicequipment. It is usually fitted with doors and/or side panels which may or may not beremovable.

cable distribution plate A component, which is used to arrange cables in order.

cable tie A tie used to bind cables.

carrier An organization that has telecom network resources and can provide communicationsservice.

carrier sense multipleaccess with collisiondetection (CSMA/CD)

Carrier sense multiple access with collision detection (CSMA/CD) is a computernetworking access method in which:

l A carrier sensing scheme is used.l A transmitting data station that detects another signal while transmitting a frame,

stops transmitting that frame, transmits a jam signal, and then waits for a randomtime interval before trying to send that frame again.

cell loss priority (CLP) A field in the ATM cell header that determines the probability of a cell being droppedif the network becomes congested. Cells with CLP = 0 are insured traffic, which isunlikely to be dropped. Cells with CLP = 1 are best-effort traffic, which might bedropped.

central processing unit(CPU)

The computational and control unit of a computer. The CPU is the device that interpretsand executes instructions. The CPU has the ability to fetch, decode, and executeinstructions and to transfer information to and from other resources over the computer'smain data-transfer path, the bus.

centralized alarm The alarms of all the hosts connecting to the Operation and Maintenance Unit (OMU).



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channel A telecommunication path of a specific capacity and/or speed between two or morelocations in a network. The channel can be established through wire, radio (microwave),fiber, or any combination of the three. The amount of information transmitted per secondin a channel is the information transmission speed, expressed in bits per second. Forexample, b/s (100 bit/s), kb/s (103 bit/s), Mb/s (106 bit/s), Gb/s (109 bit/s), and Tb/s(1012 bit/s).

channel spacing The center-to-center difference in frequencies or wavelengths between adjacent channelsin a WDM device.

check criteria A set of rules for checking and analyzing device echo information. The check criteriafor an alarm collection item need to be set through the configuration file.

circuit emulationservice (CES)

A function with which the E1/T1 data can be transmitted through ATM networks. At thetransmission end, the interface module packs timeslot data into ATM cells. These ATMcells are sent to the reception end through the ATM network. At the reception end, theinterface module re-assigns the data in these ATM cells to E1/T1 timeslots. The CEStechnology guarantees that the data in E1/T1 timeslots can be recovered to the originalsequence at the reception end.

clock selection An algorithm used for selecting the best clock for clock synchronization. For differentpeers (multiple servers or peers configured for a client), a peer sends clocksynchronization packets to each server or passive peer. After receiving the responsepackets, it uses the clock selection algorithm to select the best clock.

clock source A device that provides standard time for the NTP configuration.

clock synchronization A process of synchronizing clocks, in which the signal frequency traces the referencefrequency, but the start points do not need to be consistent. This process is (also knownas frequency synchronization).

clock tracing The method of keeping the time on each node synchronized with a clock source in thenetwork.

co-channel dualpolarization (CCDP)

A channel configuration method, which uses a horizontal polarization wave and a verticalpolarization wave to transmit two signals. The Co-Channel Dual Polarization has twicethe transmission capacity of the single polarization.

coarse wavelengthdivision multiplexing(CWDM)

A signal transmission technology that multiplexes widely-spaced optical channels intothe same fiber. CWDM spaces wavelengths at a distance of several nm. CWDM doesnot support optical amplifiers and is applied in short-distance chain networking.

collision A condition in which two packets are being transmitted over a medium at the same time.Their interference makes both unintelligible.

committed burst size(CBS)

A parameter used to define the capacity of token bucket C, that is, the maximum burstIP packet size when information is transferred at the committed information rate. Thisparameter must be greater than 0 but should be not less than the maximum length of anIP packet to be forwarded.

common spanning tree(CST)

A single spanning tree that connects all the MST regions in a network. Every MST regionis considered as a switch; therefore, the CST can be considered as their spanning treegenerated with STP/RSTP.

composite service An aggregation of a series of services relevant to each other.

conference An IP multimedia session that have two or more participants. Each conference has afocus and can be identified uniquely.



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congestion Extra intra-network or inter-network traffic resulting in decreased network serviceefficiency.

congestionmanagement

A flow control measure to solve the problem of network resource competition. Whenthe network congestion occurs, it places packets into the queue for buffer and determinesthe packet forwarding order.

connection An association of transmission channels or telecommunication circuits, switching andother functional units set up to provide for the transfer of signals between two or morenetwork points, to support a single communication.

connection admissioncontrol (CAC)

A control process in which the network takes actions in the call set-up phase (or call re-negotiation phase) to determine which connection request is admitted.

connection point A reference point where the output of a trail termination source or a connection is boundto the input of another connection, or where the output of a connection is bound to theinput of a trail termination sink or another connection. The connection point ischaracterized by the information which passes across it. A bidirectional connection pointis formed by the association of a contradirectional pair.

connectionless Pertaining to a method of data presentation. The data has a complete destination addressand is delivered by the network on a best-effort basis, independent of other data beingexchanged between the same pair of users.

constant bit rate (CBR) A kind of service categories defined by the ATM forum. CBR transfers cells based onthe constant bandwidth. It is applicable to service connections that depend on preciseclocking to ensure undistorted transmission.

container A set of hardware or software devices. In software domain, it refers to the environmentvariables and processes. In hardware domain, it refers to a type of topology node thatcontains nodes, usually refers to one device with multiple frames; each node stands fora frame.

continuity check (CC) An Ethernet connectivity fault management (CFM) method used to detect theconnectivity between MEPs by having each MEP periodically transmit a ContinuityCheck Message (CCM).

control VLAN A VLAN that transmits only protocol packets.

control channel The channel used to transmit digital control information from the base station to a cellphone or vice-versa.

convergence layer A "bridge" between the access layer and the core layer. The convergence layer providesthe convergence and forwarding functions for the access layer. It processes all the trafficfrom the access layer devices, and provides the uplinks to the core layer. Compared withthe access layer, the convergence layer devices should have higher performance, fewerinterfaces and higher switching rate. In the real network, the convergence layer refers tothe network between UPEs and PE-AGGs.

cooling system The system that controls or influences climate by decreasing the air temperature only.

core layer A layer that functions as the backbone of high speed switching for networks and provideshigh speed forwarding communications. It has a backbone transmission structure thatprovides high reliability, high throughput, and low delay. The core layer devices musthave a good redundancy, error tolerance, manageability, adaptability, and they supportdual-system hot backup or load balancing technologies. In a real network, the core layerincludes the IP/MPLS backbone network consisting of NPEs and backbone routers.



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correlation The similarities when two random processes vary with time.

corruption The alteration of the information in IMS networks for the purpose of deception. Forexample, attackers corrupt the correct charging information to evade being charged.

cross-connection The connection of channels between the tributary board and the line board, or betweenline boards inside the NE. Network services are realized through the cross-connectionsof NEs.

crossover cable A twisted pair patch cable wired in such a way as to route the transmit signals from onepiece of equipment to the receive signals of another piece of equipment, and vice versa.

crystal oscillator An oscillator that produces electrical oscillations at a frequency determined by thephysical characteristics of a piezoelectric quartz crystal.

customer edge (CE) A part of the BGP/MPLS IP VPN model that provides interfaces for directly connectingto the Service Provider (SP) network. A CE can be a router, switch, or host.

cutover To migrate the data of an application system to another application system, which thenprovides services.

cyclic redundancycheck (CRC)

A procedure used to check for errors in data transmission. CRC error checking uses acomplex calculation to generate a number based on the data transmitted. The sendingdevice performs the calculation before performing the transmission and includes thegenerated number in the packet it sends to the receiving device. The receiving devicethen repeats the same calculation. If both devices obtain the same result, the transmissionis considered to be error free. This procedure is known as a redundancy check becauseeach transmission includes not only data but extra (redundant) error-checking values.

D

D/A digital-analog converter

DB database

DC direct current

DC-C See DC-return common (with ground).

DC-I See DC-return isolate (with ground).

DC-return common(with ground) (DC-C)

A power system, in which the BGND of the DC return conductor is short-circuited withthe PGND on the output side of the power supply cabinet and also on the line betweenthe output of the power supply cabinet and the electric equipment.

DC-return isolate (withground) (DC-I)

A power system, in which the BGND of the DC return conductor is short-circuited withthe PGND on the output side of the power supply cabinet and is isolated from the PGNDon the line between the output of the power supply cabinet and the electric equipment.

DCC See data communications channel.

DCE See data circuit-terminating equipment.

DCF data communication function

DCM See dispersion compensation module.

DCN See data communication network.

DDF digital distribution frame



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DDN See digital data network.

DHCP See Dynamic Host Configuration Protocol.

DLAG See distributed link aggregation group.

DM See delay measurement.

DNI dual node interconnection

DRDB dynamic random database

DS interior node A DS node located at the center of a DS domain. It is a non-DS boundary node.

DS node A DS-compliant node, which is subdivided into DS boundary node and ID interior node.

DSCP differentiated services code point

DSL See digital subscriber line.

DSLAM See digital subscriber line access multiplexer.

DSP digital signal processing

DTE See data terminal equipment.

DTR data terminal ready

DVB digital video broadcasting

DVB-ASI digital video broadcast-asynchronous serial interface

DVMRP See Distance Vector Multicast Routing Protocol.

DWDM See dense wavelength division multiplexing.

Distance VectorMulticast RoutingProtocol (DVMRP)

An Internet gateway protocol based primarily on the RIP. The DVMRP protocolimplements a typical dense mode IP multicast solution and uses IGMP to exchangerouting datagrams with its neighbors.

Dynamic HostConfiguration Protocol(DHCP)

A client-server networking protocol. A DHCP server provides configuration parametersspecific to the DHCP client host requesting information the host requires to participateon the Internet network. DHCP also provides a mechanism for allocating IP addressesto hosts.

data backup A method of copying key data to the backup storage area to prevent data loss in case theoriginal storage area is damaged or a failure occurs.

data circuit-terminating equipment(DCE)

The equipment that provides the signal conversion and coding between the data terminalequipment (DTE) and the line. A DCE is located at a data station. The DCE may beseparate equipment, or an integral part of the DTE or intermediate equipment. The DCEmay perform other functions that are normally performed at the network end of the line.

data communicationnetwork (DCN)

A communication network used in a TMN or between TMNs to support the datacommunication function.

data communicationschannel (DCC)

The data channel that uses the D1-D12 bytes in the overhead of an STM-N signal totransmit information on the operation, management, maintenance, and provisioning(OAM&P) between NEs. The DCC channel composed of bytes D1-D3 is referred to asthe 192 kbit/s DCC-R channel. The other DCC channel composed of bytes D4-D12 isreferred to as the 576 kbit/s DCC-M channel.



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data flow A process that involves processing the data extracted from the source system, such asfiltering, integration, calculation, and summary, finding and solving data inconsistency,and deleting invalid data so that the processed data meets the requirements of thedestination system for the input data.

data mapping An algorithm that is used to convert the data between heterogeneous data models.

data restoration A method for retrieving data that is lost due to damage or misoperations.

data terminalequipment (DTE)

A user device composing the UNI. The DTE accesses the data network through the DCEequipment (for example, a modem) and usually uses the clock signals produced by DCE.

datagram A kind of protocol data unit (PDU) which is used in Connectionless Network Protocol(CLNP), such as IP datagram, UDP datagram.

defect A limited interruption in the ability of an item to perform a required function.

delay measurement(DM)

The time elapsed since the start of transmission of the first bit of the frame by a sourcenode until the reception of the last bit of the loopbacked frame by the same source node,when the loopback is performed at the frame's destination node.

demodulation In communications, the means by which a modem converts data from modulated carrierfrequencies (waves that have been modified in such a way that variations in amplitudeand frequency represent meaningful information) over a telephone line. Data is convertedto the digital form needed by a computer to which the modem is attached, with as littledistortion as possible.

dense wavelengthdivision multiplexing(DWDM)

The technology that utilizes the characteristics of broad bandwidth and low attenuationof single mode optical fiber, employs multiple wavelengths with specific frequencyspacing as carriers, and allows multiple channels to transmit simultaneously in the samefiber.

designated port A port defined in the STP protocol. On each switch that runs the STP protocol, the trafficfrom the root bridge is forwarded to the designated port. The subnet connected to theSTP switch receives the data traffic from the root bridge. All the ports on the root bridgeare designated ports. On each subnet, there is only one designated port. When a networktopology is stable, only the root port and the designated port forward traffic. Other non-designated ports are in the blocking state, and they receive STP packets, but does notforward user traffic.

destruction A process during which the information and resources in a network are changedunexpectedly and the meanings of the information and resources are deleted or changed.

digital data network(DDN)

A data transmission network that is designed to transmit data on digital channels (suchas the fiber channel, digital microwave channel, or satellite channel).

digital modulation A method that controls the changes in amplitude, phase, and frequency of the carrierbased on the changes in the baseband digital signal. In this manner, the information canbe transmitted by the carrier.

digital network A telecommunication network where information is first converted into distinctelectronic pulses and then transmitted to a digital bit stream.



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digital signal A signal in which information is represented by a limited number of discrete statesnumber of discrete states (for example, high and low voltages) rather than by fluctuatinglevels in a continuous stream, as in an analog signal. In the pulse code modulation (PCM)technology, the 8 kHz sampling frequency is used and a byte contains 8 bits in length.Therefore, a digital signal is also referred to as a byte-based code stream. Digital signals,with simple structures and broad bandwidth, are easy to shape or regenerate, and are noteasily affected by external interference.

digital subscriber line(DSL)

A technology for providing digital connections over the copper wire or the localtelephone network. DSL performs data communication over the POTS lines withoutaffecting the POTS service.

digital subscriber lineaccess multiplexer(DSLAM)

A network device, usually situated in the main office of a telephone company, thatreceives signals from multiple customer Digital Subscriber Line (DSL) connections anduses multiplexing techniques to put these signals on a high-speed backbone line.

dispersion The dependence of refraction on the wavelength of light. Different wavelengths aretransmitted in an optical medium at different speeds. Wavelengths reach the end of themedium at different times. As a result, the light pulse spreads and the dispersion occurs.

dispersioncompensation module(DCM)

A type of module that contains dispersion compensation fibers to compensate for thedispersion of the transmitting fiber.

distributed linkaggregation group(DLAG)

A board-level port protection technology that detects unidirectional fiber cuts andnegotiates with the opposite port. In the case of a link down failure on a port or hardwarefailure on a board, services are automatically switched to the slave board, therebyachieving 1+1 protection for the inter-board ports.

domain A logical subscriber group based on which the subscriber rights are controlled.

dotted decimal notation A format of IP address. IP addresses in this format are separated into four parts by a dot"." with each part is in the decimal numeral.

download To obtain data from an upper-layer device or the server.

downstream In an access network, the direction of transmission toward the subscriber end of the link.

dual-ended switching A protection method in which switching is performed at both ends of a protected entity,such as a connection or path, even if a unidirectional failure occurs.

dual-polarized antenna An antenna intended to simultaneously radiate or receive two independent radio wavesorthogonally polarized.

E

E-Aggr See Ethernet aggregation.

E-LAN See Ethernet local area network.

E-Line See Ethernet line.

EA encryption algorithm

EBS See excess burst size.

ECC See embedded control channel.

EDFA See erbium-doped fiber amplifier.



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EEPROM See electrically erasable programable read-only memory.

EF See expedited forwarding.

EFCI explicit forward congestion indication

EFM Ethernet in the First Mile

EFM OAM Ethernet in the first mile OAM

EIA See Electronic Industries Alliance.

EIR See excess information rate.

EMC See electromagnetic compatibility.

EMI See electromagnetic interference.

EMS element management system

EPD early packet discard

EPL See Ethernet private line.

EPLAN See Ethernet private LAN service.

ERPS Ethernet ring protection switching

ESC See electric supervisory channel.

ESCON See enterprise system connection.

ESD electrostatic discharge

ESN See equipment serial number.

ETS European Telecommunication Standards

ETSI See European Telecommunications Standards Institute.

EVC Ethernet virtual connection

EVPL See Ethernet virtual private line.

EVPLAN See Ethernet virtual private LAN service.

EXP See experimental bits.

Electronic IndustriesAlliance (EIA)

An association based in Washington, D.C., with members from various electronicsmanufacturers. It sets standards for electronic components. RS-232-C, for example, isthe EIA standard for connecting serial components.

EoD See Ethernet over dual domains.

Ethernet A LAN technology that uses the carrier sense multiple access with collision detection(CSMA/CD) media access control method. The Ethernet network is highly reliable andeasy to maintain. The speed of an Ethernet interface can be 10 Mbit/s, 100 Mbit/s, 1000Mbit/s, or 10,000 Mbit/s.

Ethernet aggregation(E-Aggr)

A type of Ethernet service that is based on a multipoint-to-point EVC (Ethernet virtualconnection).

Ethernet line (E-Line) A type of Ethernet service that is based on a point-to-point EVC (Ethernet virtualconnection).



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Ethernet local areanetwork (E-LAN)

A type of Ethernet service that is based on a multipoint-to-multipoint EVC (Ethernetvirtual connection).

Ethernet over dualdomains (EoD)

A type of boards. EoD boards bridge the PSN and TDM networks, enabling Ethernetservice transmission across PSN and TDM networks.

Ethernet private LANservice (EPLAN)

A type of Ethernet service provided by SDH, PDH, ATM, or MPLS server layernetworks. This service is carried over dedicated bandwidth between multipoint-to-multipoint connections.

Ethernet private line(EPL)

A type of Ethernet service provided by SDH, PDH, ATM, or MPLS server layernetworks. This service is carried over dedicated bandwidth between point-to-pointconnections.

Ethernet virtualprivate LAN service(EVPLAN)

A type of Ethernet service provided by SDH, PDH, ATM, or MPLS server layernetworks. This service is carried over shared bandwidth between multipoint-to-multipoint connections.

Ethernet virtualprivate line (EVPL)

A type of Ethernet service provided by SDH, PDH, ATM, or MPLS server layernetworks. This service is carried over shared bandwidth between point-to-pointconnections.

EuropeanTelecommunicationsStandards Institute(ETSI)

A standards-setting body in Europe. Also the standards body responsible for GSM.

eSFP enhanced small form-factor pluggable

egress The egress LER. The group is transferred along the LSP consisting of a series of LSRsafter the group is labeled.

electric supervisorychannel (ESC)

A technology that implements communication among all the nodes and transmission ofmonitoring data in an optical transmission network. The monitoring data of ESC isintroduced into DCC service overhead and is transmitted with service signals.

electrically erasableprogramable read-onlymemory (EEPROM)

A type of EPROM that can be erased with an electrical signal. It is useful for stablestorage for long periods without electricity while still allowing reprograming. EEPROMscontain less memory than RAM, take longer to reprogram, and can be reprogramed onlya limited number of times before wearing out.

electromagneticcompatibility (EMC)

A condition which prevails when telecommunications equipment is performing itsindividually designed function in a common electromagnetic environment withoutcausing or suffering unacceptable degradation due to unintentional electromagneticinterference to or from other equipment in the same environment.

electromagneticinterference (EMI)

Any electromagnetic disturbance that interrupts, obstructs, or otherwise degrades orlimits the performance of electronics/electrical equipment.

embedded controlchannel (ECC)

A logical channel that uses a data communications channel (DCC) as its physical layerto enable the transmission of operation, administration, and maintenance (OAM)information between NEs.

emergencymaintenance

A type of measure taken to quickly rectify an emergency fault to recover the properrunning of the related system or device and to reduce losses.



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encapsulation A technology for layered protocols, in which a lower-level protocol accepts a messagefrom a higher-level protocol and places it in the data portion of the lower-level frame.Protocol A's packets have complete header information, and are carried by protocol Bas data. Packets that encapsulate protocol A have a B header, an A header, followed bythe information that protocol A is carrying. Note that A could equal to B, as in IP insideIP.

engineering label A mark on a cable, a subrack, or a cabinet for identification.

enterprise systemconnection (ESCON)

A path protocol that connects the host to various control units in a storage system.Enterprise system connection is a serial bit stream transmission protocol that operates arate of 200 Mbit/s.

entity A part, device, subsystem, functional unit, equipment, or system that can be consideredindividually.

equalization A method of avoiding selective fading of frequencies. Equalization can compensate forthe changes of amplitude frequency caused by frequency selective fading.

equipment serialnumber (ESN)

A string of characters that identify a piece of equipment and ensures correct allocationof a license file to the specified equipment. It is also called "equipment fingerprint".

erbium-doped fiberamplifier (EDFA)

An optical device that amplifies optical signals. This device uses a short optical fiberdoped with the rare-earth element, Erbium. The signal to be amplified and a pump laserare multiplexed into the doped fiber, and the signal is amplified by interacting withdoping ions. When the amplifier passes an external light source pump, it amplifies theoptical signals in a specific wavelength range.

error tolerance The ability of a system or component to continue normal operation despite the presenceof erroneous inputs.

event An event indicates the information record of the status change between the system andthe managed object, including the threshold alarm of the system and the alarm reportedby the managed object.

excess burst size (EBS) A parameter related to traffic. In the single rate three color marker (srTCM) mode, trafficcontrol is achieved by token buckets C and E. The excess burst size parameter definesthe capacity of token bucket E, that is, the maximum burst IP packet size when theinformation is transferred at the committed information rate. This parameter must begreater than 0 but should be not less than the maximum length of an IP packet to beforwarded.

excess information rate(EIR)

The bandwidth for excessive or burst traffic above the CIR; it equals the result of theactual transmission rate without the safety rate.

exercise switching An operation to check whether the protection switching protocol functions properly. Theprotection switching is not really performed.

expedited forwarding(EF)

The highest order QoS in the Diff-Serv network. EF PHB is suitable for services thatdemand low packet loss ratio, short delay, and broad bandwidth. In all the cases, EFtraffic can guarantee a transmission rate equal to or faster than the set rate. The DSCPvalue of EF PHB is "101110".

experimental bits(EXP)

A field in the MPLS packet header, three bits long. This field is always used to identifythe CoS of the MPLS packet.



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extended ID The number of the subnet to which an NE belongs, used to identify different networksegments in a wide area network (WAN). Together, the ID and extended ID form thephysical ID of the NE.

external links The links between the current Web site and other Web sites. Generally, external linksrefer to links from other Web sites to the current Web site.

extract To read the data required by the destination system from the source system.

F

F1 byte The user path byte, which belongs to the family of regenerator section overhead bytes.F1 bytes are reserved for network providers, who use them primarily as a temporary dataor voice channel to transmit maintenance information.

FC See Fibre Channel.

FDB flash database

FDD See frequency division duplex.

FDDI See fiber distributed data interface.

FDI See forward defect indication.

FDI packet See forward defect indication packet.

FDV See frame delay variation.

FE port See fast Ethernet port.

FEC See forward error correction.

FFD fast failure detection

FFD packet A path failure detection method independent from CV. Different from a CV packet, thefrequency for generating FFD packets is configurable to satisfy different servicerequirements. By default, the frequency is 20/s. An FFD packet contains information thesame as that in a CV packet. The destination end LSR processes FFD packets in the sameway for processing CV packets.

FICON See Fiber Connect.

FIFO first in first out queuing

FLR See frame loss ratio.

FPGA See field programmable gate array.

FPS See fast protection switching.

FQ See flow queue.

FR See frame relay.

FRU field replaceable unit

FTN FEC to NHLFE

FTP File Transfer Protocol

Fiber Connect(FICON)

A new generation connection protocol that connects the host to various control units. Itcarries a single byte command protocol through the physical path of fiber channel, andprovides a higher transmission rate and better performance than ESCON.



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Fibre Channel (FC) A high-speed transport technology used to build SANs. FC is primarily used fortransporting SCSI traffic from servers to disk arrays, but it can also be used on networkscarrying ATM and IP traffic. FC supports single-mode and multi-mode fiberconnections, and can run on twisted-pair copper wires and coaxial cables. FC providesboth connection-oriented and connectionless services.

fairness A feature in which for any link specified in a ring network, the source node is providedwith certain bandwidth capacities if the data packets transmitted by the source node areconstrained by the fairness algorithm.

fast Ethernet port (FEport)

The port that provides a rate of 100 Mbit/s.

fast protectionswitching (FPS)

A type of pseudo wire automatic protection switching (PW APS). When the workingPW is faulty, the source transmits services to the protection PW and the sink receivesthe services from the protection PW. FPS generally works with the interworking function(IWF) to provide end-to-end protection for services.

fault A failure to operate correctly. A fault does not include failures caused by preventativemaintenance, insufficient external resources, or intentional settings.

fault alarm A type of alarm caused by hardware and/or software faults, for example, board failure,or by the exception that occurs in major functions. After handling, a fault alarm can becleared, upon which the NE reports a recovery alarm. Fault alarms are of higher severitythan event alarms.

fault detection The process of determining that a fault has occurred.

fault notification A process wherein a fault is notified. For example, when a fault occurs on the localinterface, the local interface notifies the peer of the fault through OAMPDUs. The localinterface then records the fault in the log, and reports it to the NMS.

feeder 1. A radio frequency transmission line interconnecting an antenna and a transmitter orreceiver. 2. For an antenna comprising more than one driven element, a radio frequencytransmission Line interconnecting the antenna input and a driven element.

fiber distributed datainterface (FDDI)

A standard developed by the American National Standards Institute (ANSI) for high-speed fiber-optic LANs. FDDI provides specifications for transmission rates of 100megabits per second on token ring networks.

fiber trough A trough used for routing fibers.

field programmablegate array (FPGA)

A semi-customized circuit that is used in the Application Specific Integrated Circuit(ASIC) field and developed based on programmable components. FPGA remedies manyof the deficiencies of customized circuits, and allows the use of many more gate arrays.

firewall A combination of a series of components set between different networks or networksecurity domains. By monitoring, limiting, and changing the data traffic across thefirewall, it masks the interior information, structure and running state of the network asmuch as possible to protect the network security.

fixed bandwidth The bandwidth that is fully reserved and is allocated periodically in a GPON system toensure the quality of cell transmission. If a T-CONT is provided with a fixed bandwidthand does not transmit cells, the OLT can still allocate/assign the fixed bandwidth.Therefore, idle cells are transmitted to the upstream OLT from the ONU/ONT.



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flash memory A type of special electrically erasable programmable read-only memory (EEPROM) andcan be erased and rewritten in blocks at a time instead of only one byte. The data storedin flash memory will not be lost if the flash memory is powered off.

flooding A type of incident, such as insertion of a large volume of data, that results in denial ofservice.

flow An aggregation of packets that have the same characteristics. On boards, it is a group ofpackets that have the same quality of service (QoS) operation.

flow queue (FQ) The same type of services of a user is considered one service flow. HQoS performs queuescheduling according to the services of each user. The service flows of each user areclassified into four FQs, namely, CS, EF, AF, and BE. CS is assigned a traffic shapingpercentage for Priority Queuing (PQ); EF, AF, and BE are assigned weights for WeightedFair Queuing (WFQ). The preceding two scheduling modes occupy a certain bandwidtheach; they can act at the same time without interfering each other.

forward defectindication (FDI)

A packet generated and traced forward to the sink node of the LSP by the node that firstdetects defects. It includes fields to indicate the nature of the defect and its location. Itsprimary purpose is to suppress alarms being raised at affected higher level client LSPsand (in turn) their client layers.

forward defectindication packet (FDIpacket)

A packet that responds to the detected failure event. It is used to suppress alarms of theupper layer network where failure has occurred.

forward errorcorrection (FEC)

A bit error correction technology that adds correction information to the payload at thetransmit end. Based on the correction information, the bit errors generated duringtransmission can be corrected at the receive end.

fragmentation A process of breaking a packet into smaller units when transmitting over a network nodethat does not support the original size of the packet.

frame delay variation(FDV)

A measurement of the variations in the frame delay between a pair of service frames,where the service frames belong to the same CoS instance on a point to point ETHconnection.

frame loss ratio (FLR) A ratio, is expressed as a percentage, of the number of service frames not delivereddivided by the total number of service frames during time interval T, where the numberof service frames not delivered is the difference between the number of service framesarriving at the ingress ETH flow point and the number of service frames delivered at theegress ETH flow point in a point-to-point ETH connection.

frame relay (FR) A packet-switching protocol used for WANs. Frame relay transmits variable-lengthpackets at up to 2 Mbit/s over predetermined, set paths known as PVCs (permanentvirtual circuits). It is a variant of X.25 but sacrifices X.25's error detection for the sakeof speed.

free-run mode An operating condition of a clock, the output signal of which is strongly influenced bythe oscillating element and not controlled by servo phase-locking techniques. In thismode the clock has never had a network reference input, or the clock has lost externalreference and has no access to stored data, that could be acquired from a previouslyconnected external reference. Free-run begins when the clock output no longer reflectsthe influence of a connected external reference, or transition from it. Free-run terminateswhen the clock output has achieved lock to an external reference.



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frequency divisionduplex (FDD)

An application in which channels are divided by frequency. In an FDD system, the uplinkand downlink use different frequencies. Downlink data is sent through bursts. Bothuplink and downlink transmission use frames with fixed time length.

full rate A type of data transmission rate. The service bandwidth can be 9.6 kbit/s, 4.8 kbit/s, or2.4 kbit/s.

fuse A safety device that protects an electric circuit from excessive current, consisting of orcontaining a metal element that melts when current exceeds a specific amperage, therebyopening the circuit.

G

G-ACH generic associated channel header

GAL generic associated channel header label

GCC general communication channel

GCRA generic cell rate algorithm

GFC generic flow control

GFP See Generic Framing Procedure.

GNE See gateway network element.

GPS See Global Positioning System.

GRE See Generic Routing Encapsulation.

GSM See Global System for Mobile Communications.

GTS See generic traffic shaping.

GUI graphical user interface

Generic FramingProcedure (GFP)

A framing and encapsulated method that can be applied to any data type. GFP is definedby ITU-T G.7041.

Generic RoutingEncapsulation (GRE)

A mechanism for encapsulating any network layer protocol over any other network. GREis used for encapsulating IP datagrams tunneled through the Internet. GRE serves as aLayer 3 tunneling protocol and provides a tunnel for transparently transmitting datapackets.

Global PositioningSystem (GPS)

A global navigation satellite system that provides reliable positioning, navigation, andtiming services to users worldwide.

Global System forMobileCommunications(GSM)

The second-generation mobile networking standard defined by EuropeanTelecommunications Standards Institute (ETSI). It is aimed at designing a standard forglobal mobile phone networks. The standard allows a subscriber to use a phone globally.GSM consists of three main parts: mobile switching subsystem (MSS), base stationsubsystem (BSS), and mobile station (MS).

gain The difference between the optical power from the input optical interface of the opticalamplifier and the optical power from the output optical interface of the jumper fiber,which expressed in dB.

gateway A device that connects two network segments using different protocols. It is used totranslate the data in the two network segments.



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gateway networkelement (GNE)

An NE that serves as a gateway for other NEs to communicate with a networkmanagement system.

general flow control A flow control that is applicable to the A interface, C/D interface, and trunks and can beachieved by integrating multiple function modules. It is adopted when the traffic is heavy,or location update and authentication of multiple subscribers are performed after thesystem restarts. It can efficiently prevent system breakdown caused by link congestionor CPU overload.

generic traffic shaping(GTS)

A traffic control measure that proactively adjusts the output speed of the traffic. This isto adapt the traffic to network resources that can be provided by the downstream routerto avoid packet discarding and congestion.

ground terminal A connection terminal on a communication device. It is used to connect the device withground cables, maintaining a tight connection between the device and the groundingelectrode.

H

HCS higher order connection supervision

HDB3 high density bipolar of order 3 code

HDLC High-Level Data Link Control

HDTV See high definition television.

HEC See header error control.

HPA higher order path adaptation

HPT higher order path termination

HQoS See hierarchical quality of service.

HSDPA See High Speed Downlink Packet Access.

HSI high-speed Internet

High Speed DownlinkPacket Access(HSDPA)

A modulating-demodulating algorithm put forward in 3GPP R5 to meet the requirementfor asymmetric uplink and downlink transmission of data services. It enables themaximum downlink data service rate to reach 14.4 Mbit/s without changing theWCDMA network topology.

hang up A call processing mode used by an attendant to end the conversation with a user.

hardware loopback A connection mode in which a fiber jumper is used to connect the input optical interfaceof a board to the output optical interface of the board to achieve signal loopback.

header error control(HEC)

A field within the ATM frame whose purpose is to correct any single bit error in the cellHeader and also to detect any multi-bit errors. It actually performs a CRC check in thefirst four header bits and also at the receiving end.

hello packet The commonest packet which is periodically sent by a router to its neighbors. It containsinformation about the DR, Backup Designated Router (BDR), known neighbors andtimer values.



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hierarchical quality ofservice (HQoS)

A type of QoS that controls the traffic of users and performs the scheduling accordingto the priority of user services. HQoS has an advanced traffic statistics function, and theadministrator can monitor the usage of bandwidth of each service. Hence, the bandwidthcan be allocated reasonably through traffic analysis.

high definitiontelevision (HDTV)

A type of TV that is capable of displaying at least 720 progressive or 1080 interlacedactive scan lines. It must be capable of displaying a 16:9 image using at least 540progressive or 810 interlaced active scan lines.

historical performancedata

Performance data that is stored in the history register or that has been automaticallyreported and stored in the NMS.

hop A network connection between two distant nodes. For Internet operation a hop representsa small step on the route from one main computer to another.

hot patch A patch that is used to repair a deficiency in the software or add a new feature to a programwithout restarting the software and interrupting the service. For the equipment using thebuilt-in system, a hot patch can be loaded, activated, confirmed, deactivated, deleted, orqueried.

I

IANA See Internet Assigned Numbers Authority.

IC See integrated circuit.

ICC ITU carrier code

ICMP See Internet Control Message Protocol.

ICP IMA Control Protocol

IDU See indoor unit.

IEEE See Institute of Electrical and Electronics Engineers.

IF See intermediate frequency.

IGMP See Internet Group Management Protocol.

IGMP snooping A multicast constraint mechanism running on a layer 2 device. This protocol managesand controls the multicast group by listening to and analyzing Internet GroupManagement Protocol (IGMP) packets between hosts and Layer 3 devices. In thismanner, the spread of the multicast data on layer 2 network can be prevented efficiently.

IGP See Interior Gateway Protocol.

ILM incoming label map

IMA See inverse multiplexing over ATM.

IMA frame A control unit in the IMA protocol. It is a logical frame defined as M consecutive cells,numbered 0 to M-l, transmitted on each of the N links in an IMA group.

IP Internet Protocol

IP address A 32-bit (4-byte) binary number that uniquely identifies a host connected to the Internet.An IP address is expressed in dotted decimal notation, consisting of the decimal valuesof its 4 bytes, separated with periods; for example, 127.0.0.1. The first three bytes of theIP address identify the network to which the host is connected, and the last byte identifiesthe host itself.



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IPA See intelligent power adjustment.

IPTV See Internet Protocol television.

IPv4 See Internet Protocol version 4.

IPv6 See Internet Protocol version 6.

IS-IS See Intermediate System to Intermediate System.

ISDN integrated services digital network

ISO International Organization for Standardization

ISP See Internet service provider.

IST internal spanning tree

ITC independent transmit clock

ITU See International Telecommunication Union.

IWF Interworking Function

Institute of Electricaland ElectronicsEngineers (IEEE)

A professional association of electrical and electronics engineers based in the UnitedStates, but with membership from numerous other countries. The IEEE focuses onelectrical, electronics, and computer engineering, and produces many importanttechnology standards.

Interior GatewayProtocol (IGP)

A routing protocol that is used within an autonomous system. The IGP runs in small-sized and medium-sized networks. The commonly used IGPs are the routing informationprotocol (RIP), the interior gateway routing protocol (IGRP), the enhanced IGRP(EIGRP), and the open shortest path first (OSPF).

Intermediate System toIntermediate System(IS-IS)

A protocol used by network devices (routers) to determine the best way to forwarddatagram or packets through a packet-based network.

InternationalTelecommunicationUnion (ITU)

A United Nations agency, one of the most important and influential recommendationbodies, responsible for recommending standards for telecommunication (ITU-T) andradio networks (ITU-R).

Internet AssignedNumbers Authority(IANA)

A department operated by the IAB. IANA delegates authority for IP address-spaceallocation and domain-name assignment to the NIC and other organizations. IANA alsomaintains a database of assigned protocol identifiers used in the TCP/IP suite, includingautonomous system numbers.

Internet ControlMessage Protocol(ICMP)

A network layer protocol that provides message control and error reporting between ahost server and an Internet gateway.

Internet GroupManagement Protocol(IGMP)

One of the TCP/IP protocols for managing the membership of Internet Protocol multicastgroups. It is used by IP hosts and adjacent multicast routers to establish and maintainmulticast group memberships.

Internet Protocoltelevision (IPTV)

A system that provides TV services over the IP network. In the IPTV system, mediastreams from satellites, terrestrial, and studios are converted by the encoder to the mediastreams applicable to the IP network. Then the media streams are transmitted to theterminal layer on the IP network. Media content is displayed on a TV set after mediastreams are processed by specified receiving devices (for example, an STB).



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Internet Protocolversion 4 (IPv4)

The current version of the Internet Protocol (IP). IPv4 utilizes a 32bit address which isassigned to hosts. An address belongs to one of five classes (A, B, C, D, or E) and iswritten as 4 octets separated by periods and may range from 0.0.0.0 through to255.255.255.255. Each IPv4 address consists of a network number, an optionalsubnetwork number, and a host number. The network and subnetwork numbers togetherare used for routing, and the host number is used to address an individual host within thenetwork or subnetwork.

Internet Protocolversion 6 (IPv6)

An update version of IPv4, which is designed by the Internet Engineering Task Force(IETF) and is also called IP Next Generation (IPng). It is a new version of the InternetProtocol. The difference between IPv6 and IPv4 is that an IPv4 address has 32 bits whilean IPv6 address has 128 bits.

Internet serviceprovider (ISP)

An organization that offers users access to the Internet and related services.

inbound Data transmission from the external link to the router for the routers that support theNetStream feature.

indicator Description of a performance feature collected from the managed devices by theperformance collector.

indoor unit (IDU) The indoor unit of the split-structured radio equipment. It implements accessing,multiplexing/demultiplexing, and intermediate frequency (IF) processing for services.

input jitter tolerance The measure of a receiver's ability to tolerate jitter on an incoming waveform.

insertion loss The loss of power that results from inserting a component, such as a connector, coupler,or splice, into a previously continuous path.

integrated circuit (IC) A combination of inseparable associated circuit elements that are formed in place andinterconnected on or within a single base material to perform a microcircuit function.

intelligent poweradjustment (IPA)

A technology that reduces the optical power of all the amplifiers in an adjacentregeneration section in the upstream to a safe level if the system detects the loss of opticalsignals on the link. IPA helps ensure that maintenance engineers are not injured by thelaser escaping from a broken fiber or a connector that is not plugged in properly.

interleaving A process of systematically changing the bit sequence of a digital signal, usually as partof the channel coding, in order to reduce the influence of error bursts that may occurduring transmission.

intermediate frequency(IF)

The transitional frequency between the frequencies of a modulated signal and an RFsignal.

inverse multiplexingover ATM (IMA)

A technique that involves inverse multiplexing and de-multiplexing of ATM cells in acyclical fashion among links grouped to form a higher bandwidth logical link whose rateis approximately the sum of the link rates.

J

jitter The measure of short waveform variations caused by vibration, voltage fluctuations, andcontrol system instability.

jumper A connection wire for connecting two pins.

K



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K byte A general designation of K1 byte and K2 byte in the SDH.

L

L2 switching The switching based on the data link layer.

L2VPN Layer 2 virtual private network

LACP See Link Aggregation Control Protocol.

LACPDU Link Aggregation Control Protocol data unit

LAG See link aggregation group.

LAN See local area network.

LAPS Link Access Protocol-SDH

LB See loopback.

LBM See loopback message.

LBR See loopback reply.

LC Lucent connector

LCAS See link capacity adjustment scheme.

LCN local communications network

LCT local craft terminal

LDP Label Distribution Protocol

LED See light emitting diode.

LER See label edge router.

LIFO See last in first out.

LIU logical interface unit

LL logical link

LLC See logical link control.

LLID local loopback ID

LM See loss measurement.

LOC loss of continuity

LOM loss of multiframe

LOP loss of pointer

LOS See loss of signal.

LP lower order path

LPA lower order path adaptation

LPF See low-pass filter.

LPT link-state pass through

LSP See label switched path.



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LSR See label switching router.

LT linktrace

LTM See linktrace message.

LTR See linktrace reply.

LU line unit

Layer 2 switching A data forwarding method. In a LAN, a network bridge or 802.3 Ethernet switchtransmits and distributes packet data based on the MAC address. Since the MAC addressis at the second layer of the OSI model, this data forwarding method is called Layer 2switching.

Link AggregationControl Protocol(LACP)

A dynamic link aggregation protocol that improves the transmission speed andreliability. The two ends of the link send LACP packets to inform each other of theirparameters and form a logical aggregation link. After the aggregation link is formed,LACP maintains the link status in real time and dynamically adjusts the ports on theaggregation link upon detecting the failure of a physical port.

label A short identifier that is of fixed length and local significance. It is used to uniquelyidentify the FEC to which a packet belongs. It does not contain topology information. Itis carried in the header of a packet and does not contain topology information.

label distribution Packets with the same destination address belong to an FEC. A label out of an MPLSlabel resource pool is allocated to the FEC. LSRs record the relationship of the label andthe FEC. Then, LSRs sends a message and advertises to upstream LSRs about the labeland FEC relationship in message. The process is called label distribution.

label edge router (LER) A device that sits at the edge of an MPLS domain, that uses routing information to assignlabels to datagrams and then forwards them into the MPLS domain.

label space Value range of the label allocated to peers.

label switched path(LSP)

A sequence of hops (R0...Rn) in which a packet travels from R0 to Rn through labelswitching mechanisms. A label-switched path can be chosen dynamically, based oncommon routing mechanisms or through configuration.

label switching router(LSR)

Basic element of an MPLS network. All LSRs support the MPLS protocol. The LSR iscomposed of two parts: control unit and forwarding unit. The former is responsible forallocating the label, selecting the route, creating the label forwarding table, creating andremoving the label switch path; the latter forwards the labels according to groupsreceived in the label forwarding table.

laser A component that generates directional optical waves of narrow wavelengths. The laserlight has better coherence than ordinary light. Semi-conductor lasers provide the lightused in a fiber system.

last in first out (LIFO) A play mode of the voice mails, the last voice mail is played firstly.

layer A concept used to allow transport network functionality to be described hierarchicallyas successive levels; each layer being solely concerned with the generation and transferof its characteristic information.

license A permission that the vendor provides for the user with a specific function, capacity, andduration of a product. A license can be a file or a serial number. Usually the licenseconsists of encrypted codes. The operation authority granted varies with the level of thelicense.



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light emitting diode(LED)

A display and lighting technology used in almost every electrical and electronic producton the market, from a tiny on/off light to digital readouts, flashlights, traffic lights, andperimeter lighting. LEDs are also used as the light source in multimode fibers, opticalmice, and laser printers.

line rate The maximum packet forwarding capacity on a cable. The value of line rate equals themaximum transmission rate capable on a given type of media.

linear MSP linear multiplex section protection

link aggregation group(LAG)

An aggregation that allows one or more links to be aggregated together to form a linkaggregation group so that a MAC client can treat the link aggregation group as if it werea single link.

link capacityadjustment scheme(LCAS)

LCAS in the virtual concatenation source and sink adaptation functions provides acontrol mechanism to hitless increase or decrease the capacity of a link to meet thebandwidth needs of the application. It also provides a means of removing member linksthat have experienced failure. The LCAS assumes that in cases of capacity initiation,increases or decreases, the construction or destruction of the end-to-end path is theresponsibility of the network and element management systems.

link monitoring A mechanism for an interface to notify the peer of the fault when the interface detectsthat the number of errored frames, errored codes, or errored frame seconds reaches orexceeds the specified threshold.

link protection Protection provided by the bypass tunnel for the link on the working tunnel. The link isa downstream link adjacent to the point of local repair (PLR). When the PLR fails toprovide node protection, the link protection should be provided.

linktrace message(LTM)

The message sent by the initiator MEP of 802.1ag MAC Trace to the destination MEP.LTM includes the Time to Live (TTL) and the MAC address of the destination MEP2.

linktrace reply (LTR) For 802.1ag MAC Trace, the destination MEP replies with a response message to thesource MEP after the destination MEP receives the LTM, and the response message iscalled LTR. LTR also includes the TTL that equals the result of the TTL of LTM minus1.

load balancing The distribution of activity across two or more servers or components in order to avoidoverloading any one with too many requests or too much traffic.

loading A process of importing information from the storage device to the memory to facilitateprocessing (when the information is data) or execution (when the information isprogram).

local MEP An MEP of a device on a network enabled with Ethernet CFM.

local area network(LAN)

A network formed by the computers and workstations within the coverage of a few squarekilometers or within a single building, featuring high speed and low error rate. CurrentLANs are generally based on switched Ethernet or Wi-Fi technology and run at 1,000Mbit/s (that is, 1 Gbit/s).

logical interface An interface that does not exist physically and comes into being through configuration.It can also exchange data.

logical link control(LLC)

According to the IEEE 802 family of standards, Logical Link Control (LLC) is the uppersublayer of the OSI data link layer. The LLC is the same for the various physical media(such as Ethernet, token ring, WLAN).



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loopback (LB) A troubleshooting technique that returns a transmitted signal to its source so that thesignal or message can be analyzed for errors. The loopback can be a inloop or outloop.

loopback message(LBM)

The loopback packet sent by the node that supports 802.2ag MAC Ping to the destinationnode. LBM message carries its own sending time.

loopback reply (LBR) A response message involved in the 802.2ag MAC Ping function, with which thedestination MEP replies to the source MEP after the destination MEP receives the LBM.The LBR carries the sending time of LBM, the receiving time of LBM and the sendingtime of LBR.

loss measurement (LM) A method used to collect counter values applicable for ingress and egress service frameswhere the counters maintain a count of transmitted and received data frames between apair of MEPs.

loss of signal (LOS) No transitions occurring in the received signal.

low-pass filter (LPF) A filter designed to transmit electromagnetic frequencies below a certain value, whileexcluding those of a higher frequency.

lower threshold A lower performance limit which when exceeded by a performance event counter willtrigger a threshold-crossing event.

M

MA maintenance association

MAC See Media Access Control.

MAC address A link layer address or physical address. It is six bytes long.

MAC address aging A function that deletes MAC address entries of a device when no packets are receivedfrom this device within a specified time period.

MADM multiple add/drop multiplexer

MAN See metropolitan area network.

MBS maximum burst size

MCF message communication function

MCR minimum cell rate

MD See maintenance domain.

MDP message dispatch process

ME See maintenance entity.

MEG maintenance entity group

MEL maintenance entity group level

MEP See maintenance entity group end point.

MFAS See multiframe alignment signal.

MIP See maintenance entity group intermediate point.

MLD See multicast listener discovery.

MP maintenance point



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MPID maintenance point identification

MPLS See Multiprotocol Label Switching.

MPLS TE multiprotocol label switching traffic engineering

MPLS VPN See multiprotocol label switching virtual private network.

MS multiplex section

MSA multiplex section adaptation

MSB most significant bit

MSOH multiplex section overhead

MSP See multiplex section protection.

MST See multiplex section termination.

MST region See Multiple Spanning Tree region.

MSTI See multiple spanning tree instance.

MSTP See Multiple Spanning Tree Protocol.

MTBF See mean time between failures.

MTIE maximum time interval error

MTTR See mean time to repair.

MTU See maximum transmission unit.

MUX See multiplexer.

Media Access Control(MAC)

A protocol at the media access control sublayer. The protocol is at the lower part of thedata link layer in the OSI model and is mainly responsible for controlling and connectingthe physical media at the physical layer. When transmitting data, the MAC protocolchecks whether to be able to transmit data. If the data can be transmitted, certain controlinformation is added to the data, and then the data and the control information aretransmitted in a specified format to the physical layer. When receiving data, the MACprotocol checks whether the information is correct and whether the data is transmittedcorrectly. If the information is correct and the data is transmitted correctly, the controlinformation is removed from the data and then the data is transmitted to the LLC layer.

Multiple SpanningTree Protocol (MSTP)

A protocol that can be used in a loop network. Using an algorithm, the MSTP blocksredundant paths so that the loop network can be trimmed as a tree network. In this case,the proliferation and endless cycling of packets is avoided in the loop network. Theprotocol that introduces the mapping between VLANs and multiple spanning trees. Thissolves the problem that data cannot be normally forwarded in a VLAN because in STP/RSTP, only one spanning tree corresponds to all the VLANs.

Multiple SpanningTree region (MSTregion)

A region that consists of switches that support the MSTP in the LAN and links amongthem. Switches physically and directly connected and configured with the same MSTregion attributes belong to the same MST region.

Multiprotocol LabelSwitching (MPLS)

A technology that uses short tags of fixed length to encapsulate packets in different linklayers, and provides connection-oriented switching for the network layer on the basis ofIP routing and control protocols.



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main topology A basic component of a human-machine interface. It is the default client interface of theNMS and intuitively displays the structure of a network, NEs on the network, subnets inthe network as well as the NE communication and running status, reflecting the overallnetwork running status.

maintenance domain(MD)

The network or the part of the network for which connectivity is managed by connectivityfault management (CFM). The devices in a maintenance domain are managed by a singleInternet service provider (ISP).

maintenance entity(ME)

An ME consists of a pair of maintenance entity group end points (MEPs), two ends of atransport trail, and maintenance association intermediate points (MIPs) on the trail.

maintenance entitygroup end point (MEP)

An end point of a MEG, which is able to initialize and stop the transmission of OAMdata packets for fault management and performance monitoring.

maintenance entitygroup intermediatepoint (MIP)

An intermediate point in a MEG, which is able to forward OAM packets and respond tosome OAM packets, but unable to initiate the transmission of OAM packets or performany operations on network connections.

managementinformation

The information that is used for network management in a transport network.

maximum transmissionunit (MTU)

The largest packet of data that can be transmitted on a network. MTU size varies,depending on the network—576 bytes on X.25 networks, for example, 1500 bytes onEthernet, and 17,914 bytes on 16 Mbit/s token ring. Responsibility for determining thesize of the MTU lies with the link layer of the network. When packets are transmittedacross networks, the path MTU, or PMTU, represents the smallest packet size (the onethat all networks can transmit without breaking up the packet) among the networksinvolved.

mean time betweenfailures (MTBF)

The average time between consecutive failures of a piece of equipment. It is a measureof the reliability of the system.

mean time to repair(MTTR)

The average time that a device will take to recover from a failure.

measurement period The interval for NEs to report measurement results to the Network Management System(NMS).

medium A physical medium for storing computer information. A medium is used for dataduplication and keeping the data for some time. Original data can be obtained from amedium.

member A basic element for forming a dimension according to the hierarchy of each level. Eachmember represents a data element in a dimension. For example, January 1997 is a typicalmember of the time dimension.

metropolitan areanetwork (MAN)

A medium-scale computer network with area larger than that covered by a LAN andsmaller than that covered by a WAN. It interconnects multiple LAN networks in ageographic region of a city.

microwave The portion of the electromagnetic spectrum with much longer wavelengths than infraredradiation, typically above about 1 mm.

mirroring The duplication of data for backup or to distribute network traffic among severalcomputers with identical data.



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monitoring A method that an inspector uses to inspect a service agent. By monitoring a service agent,an inspector can check each detailed operation performed by the service agent duringthe conversation and operate the GUI used by the service agent. The inspector helps theservice agent to provide better service.

mounting An auxiliary or associated condition or component of a device.

mounting ear A piece of angle plate on a rack. The mounting ear has holes that can be used to fixnetwork elements or components.

multicast A process of transmitting data packets from one source to many destinations. Thedestination address of the multicast packet uses Class D address, that is, the IP addressranges from 224.0.0.0 to 239.255.255.255. Each multicast address represents a multicastgroup rather than a host.

multicast listenerdiscovery (MLD)

A protocol used by an IPv6 router to discover the multicast listeners on their directlyconnected network segments, and to set up and maintain member relationships. On IPv6networks, after MLD is configured on the receiver hosts and the multicast router to whichthe hosts are directly connected, the hosts can dynamically join related groups and themulticast router can manage members on the local network.

multiframe alignmentsignal (MFAS)

A distinctive signal inserted into every multiframe or once into every n multiframes,always occupying the same relative position within the multiframe, and used to establishand maintain multiframe alignment.

multiple spanning treeinstance (MSTI)

A type of spanning trees calculated by MSTP within an MST Region, to provide a simplyand fully connected active topology for frames classified as belonging to a VLAN thatis mapped to the MSTI by the MST Configuration. A VLAN cannot be assigned tomultiple MSTIs.

multiplex sectionprotection (MSP)

A function, which is performed to provide capability for switching a signal between andincluding two multiplex section termination (MST) functions, from a "working" to a"protection" channel.

multiplex sectiontermination (MST)

A function that generates the multiplex section overhead (MSOH) during the formationof an SDH frame signal and that terminates the MSOH in the reverse direction.

multiplexer (MUX) Equipment that combines a number of tributary channels onto a fewer number ofaggregate bearer channels, the relationship between the tributary and aggregate channelsbeing fixed.

multiplexing A procedure by which multiple lower order path layer signals are adapted into a higherorder path or the multiple higher order path layer signals are adapted into a multiplexsection.

multiprotocol labelswitching virtualprivate network(MPLS VPN)

An Internet Protocol (IP) virtual private network (VPN) based on the multiprotocol labelswitching (MPLS) technology. It applies the MPLS technology for network routers andswitches, simplifies the routing mode of core routers, and combines traditional routingtechnology and label switching technology. It can be used to construct the broadbandIntranet and Extranet to meet various service requirements.

N

N+1 protection A radio link protection system composed of N working channels and one protectionchannel.

NAS network access server



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NC See NTP client.

NE ID An ID that indicates a managed device in the network. In the network, each NE has aunique NE ID.

NGN See next generation network.

NHLFE next hop label forwarding entry

NLP normal link pulse

NM network management

NMC network management center

NNI network-to-network interface

NP See network processor.

NPC See network parameter control.

NPE network provider edge

NRT-VBR non-real-time variable bit rate

NRZ non-return to zero

NRZ code non-return-to-zero code

NRZI non-return to zero inverted

NSAP See network service access point.

NSF non-stop forwarding

NTP Network Time Protocol

NTP client (NC) A bottom-level device in the time synchronization network. An NTP client obtains timefrom its upper-level NTP server without providing the time synchronization service.Compared with the top-level NTP server, the intermediate NTP server sometimes iscalled an NTP client.

network layer Layer 3 of the seven-layer OSI model of computer networking. The network layerprovides routing and addressing so that two terminal systems are interconnected. Inaddition, the network layer provides congestion control and traffic control. In the TCP/IP protocol suite, the functions of the network layer are specified and implemented byIP protocols. Therefore, the network layer is also called IP layer.

network parametercontrol (NPC)

During communications, UPC is implemented to monitor the actual traffic on each virtualcircuit that is input to the network. Once the specified parameter is exceeded, measureswill be taken to control. NPC is similar to UPC in function. The difference is that theincoming traffic monitoring function is divided into UPC and NPC according to theirpositions. UPC locates at the user/network interface, while NPC at the network interface.

network processor (NP) An integrated circuit which has a feature set specifically targeted at the networkingapplication domain. Network Processors are typically software programmable devicesand would have generic characteristics similar to general purpose CPUs that arecommonly used in many different types of equipment and products.

network segment Part of a network on which all message traffic is common to all nodes; that is, a messagebroadcast from one node on the segment is received by all other nodes on the segment.

network service A service that needs to be enabled at the network layer and maintained as a basic service.



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network service accesspoint (NSAP)

A network address defined by ISO, at which the OSI Network Service is made availableto a Network service user by the Network service provider.

network storm A phenomenon that occurs during data communication. To be specific, mass broadcastpackets are transmitted in a short time; the network is congested; transmission qualityand availability of the network decrease rapidly. The network storm is caused by networkconnection or configuration problems.

next generationnetwork (NGN)

A packet-based network aimed to address requirement of various services. It adopts anintegrated and open network framework. In NGN, services are separated from callcontrol; call control is separated from bearer. In this way, services are independent ofnetwork. NGN can provide various services, such as voice services, data services,multimedia services or the integration of several services.

noise figure A measure of degradation of the signal-to-noise ratio (SNR), caused by components ina radio frequency (RF) signal chain. The noise figure is defined as the ratio of the outputnoise power of a device to the portion thereof attributable to thermal noise in the inputtermination at standard noise temperature T0 (usually 290 K). The noise figure is thusthe ratio of actual output noise to that which would remain if the device itself did notintroduce noise. It is a number by which the performance of a radio receiver can bespecified.

non-GNE See non-gateway network element.

non-gateway networkelement (non-GNE)

A network element that communicates with the NM application layer through thegateway NE application layer.

O

O&M operation and maintenance

OA optical amplifier

OADM See optical add/drop multiplexer.

OAM See operation, administration and maintenance.

OAMPDU operation, administration and maintenance protocol data unit

OAU See optical amplifier unit.

OC ordinary clock

OCP optical channel protection

OCS optical core switching

ODF optical distribution frame

ODU See outdoor unit.

OFS out-of-frame second

OHA overhead access

OHP overhead processing

OLT optical line terminal

ONU See optical network unit.

OPEX operating expense



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OPU optical channel payload unit

OSC See optical supervisory channel.

OSN optical switch node

OSNR See optical signal-to-noise ratio.

OSPF See Open Shortest Path First.

OTDR See optical time domain reflectometer.

OTM optical terminal multiplexer

OTN optical transport network

OTU See optical transponder unit.

OTUk optical channel transport unit - k

Open Shortest PathFirst (OSPF)

A link-state, hierarchical interior gateway protocol (IGP) for network routing that usescost as its routing metric. A link state database is constructed of the network topology,which is identical on all routers in the area.

offline Pertaining to the disconnection between a device or a service unit and the system or thenetwork, or no running of a device and service unit.

online A state indicating that a computer device or program is activated and is ready foroperations, and can communicate with a computer or can be controlled by the computer.

operation,administration andmaintenance (OAM)

A set of network management functions that cover fault detection, notification, location,and repair.

optical add/dropmultiplexer (OADM)

A device that can be used to add the optical signals of various wavelengths to one channeland drop the optical signals of various wavelengths from one channel.

optical amplifier unit(OAU)

A board that is mainly responsible for amplifying optical signals. The OAU can be usedin both the transmitting direction and the receiving direction.

optical attenuator A passive device that increases the attenuation in a fiber link. An optical attenuator isused to ensure that the optical power of a signal at the receive end is not excessivelyhigh.

optical connector A component attached to the end of an optical fiber that allows the fiber to connect toanother fiber or an optical source.

optical fiber A thin filament of glass or other transparent material, through which a signal-encodedlight beam may be transmitted using total internal reflection.

optical interface A component that connects several transmit or receive units.

optical network unit(ONU)

A form of Access Node that converts optical signals transmitted via fiber to electricalsignals that can be transmitted via coaxial cable or twisted pair copper wiring toindividual subscribers.

optical signal-to-noiseratio (OSNR)

The ratio of signal power to noise power in a transmission link. OSNR is the mostimportant index for measuring the performance of a DWDM system.



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optical splitter A passive component, which is used for splitting and sending optical power to multipleONUs connected by an optical fiber. In a GPON system that consists of the OLT, ONU,splitter, and optical fibers, according to the split ratio, the optical signal over the opticalfiber connected to the OLT is splitted into multiple channels of optical signals and sendeach channel to each ONU. Split ratio determines how many channels of optical signalsan optical fiber can be split to.

optical supervisorychannel (OSC)

A technology that uses specific optical wavelengths to realize communication amongnodes in optical transmission network and transmit the monitoring data in a certainchannel.

optical time domainreflectometer (OTDR)

A device that sends a series of short pulses of light down a fiber-optic cable and measuresthe strength of the return pulses. An OTDR is used to measure fiber length and light loss,and to locate fiber faults.

optical transponderunit (OTU)

A device or subsystem that converts accessed client signals into a G.694.1/G.694.2-compliant WDM wavelength.

orderwire A channel that provides voice communication between operation engineers ormaintenance engineers of different stations.

outdoor unit (ODU) The outdoor unit of the split-structured radio equipment. It implements frequencyconversion and amplification for radio frequency (RF) signals.

P

P2MP point-to-multipoint

P2P See point-to-point service.

PA power amplifier

PADR PPPoE active discovery request

PBS See peak burst size.

PCB See printed circuit board.

PCM See pulse code modulation.

PCR See peak cell rate.

PCS physical coding sublayer

PDH See plesiochronous digital hierarchy.

PDU See power distribution unit.

PE See provider edge.

PGND cable A cable which connects the equipment and the protection grounding bar. Usually, onehalf of the cable is yellow, whereas the other half is green.

PHB See per-hop behavior.

PIM-DM Protocol Independent Multicast - Dense Mode

PIM-SM Protocol Independent Multicast - Sparse Mode

PKT partition knowledge table

PLL See phase-locked loop.



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PM performance monitoring

PMD polarization mode dispersion

POH path overhead

POS See packet over SDH/SONET.

PPD partial packet discard

PPI PDH physical interface

PPP Point-to-Point Protocol

PPPoE Point-to-Point Protocol over Ethernet

PPS port protection switching

PQ See priority queuing.

PRBS See pseudo random binary sequence.

PRC primary reference clock

PSD See power spectrum density.

PSN See packet switched network.

PSTN See public switched telephone network.

PSU power supply unit

PT payload type

PTI payload type indicator

PTN packet transport network

PTP Precision Time Protocol

PVC permanent virtual channel

PVID See port default VLAN ID.

PVP See permanent virtual path.

PW See pseudo wire.

PWE3 See pseudo wire emulation edge-to-edge.

packet discarding A function of discarding the packets from unknown VLAN domain or broadcast packets.Packet Discarding is used to prevent the situation where unknown packets or broadcastpackets use the bandwidth on a link, improving the reliability of service transmission.

packet forwarding An action performed by a router to forward a received datagram, where the destinationIP address does not match the IP address of the router, to another router or destinationhost on the router list.

packet loss The discarding of data packets in a network when a device is overloaded and cannotaccept any incoming data at a given moment.

packet over SDH/SONET (POS)

A MAN and WAN technology that provides point-to-point data connections. The POSinterface uses SDH/SONET as the physical layer protocol, and supports the transport ofpacket data (such as IP packets) in MAN and WAN.



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packet rate The number of bits or bytes passed within a specified time. It is expressed in bits/s orbytes/s.

packet switchednetwork (PSN)

A telecommunications network that works in packet switching mode.

packet switching A network technology in which information is transmitted by means of exchangingpackets and the bandwidth of a channel can be shared by multiple connections.

paired slots Two slots of which the overheads can be passed through by using the bus on thebackplane.

parity bit A check bit appended to an array of binary digits to make the sum of all the binary digits,including the check bit, always odd or always even.

parity check A method for character level error detection. An extra bit is added to a string of bits,usually a 7-bit ASCII character, so that the total number of bits 1 is odd or even (odd oreven parity). Both ends of a data transmission must use the same parity. When thetransmitting device frames a character, it counts the numbers of 1s in the frame andattaches the appropriate parity bit. The recipient counts the 1s and, if there is parity error,may ask for the data to be retransmitted.

parts replacement A maintenance operation of removing a faulty part or a part to be examined from arunning device and then installing a new part.

passive mode A working mode of EFM OAM. An interface in the passive mode cannot initiate thediscovery and remote loopback.

patch An independent software unit used for fixing the bugs in software.

peak burst size (PBS) A parameter that defines the capacity of token bucket P, that is, the maximum burst IPpacket size when the information is transferred at the peak information rate.

peak cell rate (PCR) The maximum rate at which an ATM connection can accept cells.

peer BGP speakers that exchange information with each other.

per-hop behavior(PHB)

IETF Diff-Serv workgroup defines forwarding behaviors of network nodes as per-hopbehaviors (PHB), such as, traffic scheduling and policing. A device in the network shouldselect the proper PHB behaviors, based on the value of DSCP. At present, the IETFdefines four types of PHB. They are class selector (CS), expedited forwarding (EF),assured forwarding (AF), and best-effort (BE).

performance alarm An alarm generated when the actual result of a measurement entity equals the predefinedlogical expression for threshold or exceeds the predefined threshold.

performanceparameters

The performance parameters identify some indexes to scale the general performance ofthe system. The indexes include the number of managed nodes, number of supportedclients and log database capacity. The parameters are sorted into static parameters,dynamic parameters and networking bandwidth parameters.

performance register The memory space for performance event counts, including 15-min current performanceregister, 24-hour current performance register, 15-min historical performance register,24-hour historical performance register, UAT register and CSES register. The object ofperformance event monitoring is the board functional module, so every board functionalmodule has a performance register. A performance register is used to count theperformance events taking place within a period of operation time, so as to evaluate thequality of operation from the angle of statistics.



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performance threshold A limit for generating an alarm for a selected entity. When the measurement resultreaches or exceeds the preset alarm threshold, the performance management systemgenerates a performance alarm.

permanent virtual path(PVP)

Virtual path that consists of PVCs.

phase The relative position in time within a single period of a signal.

phase-locked loop(PLL)

A circuit that consists essentially of a phase detector that compares the frequency of avoltage-controlled oscillator with that of an incoming carrier signal or reference-frequency generator. The output of the phase detector, after passing through a loop filter,is fed back to the voltage-controlled oscillator to keep it exactly in phase with theincoming or reference frequency.

physical layer Layer 1 in the Open System Interconnection (OSI) architecture; the layer that providesservices to transmit bits or groups of bits over a transmission link between open systemsand which entails electrical, mechanical and handshaking.

physical link The link between two physical network elements (NEs). When the user creates NEs orrefreshes the device status, the system automatically creates the physical link accordingto the topology structure information on the device. The remark information of a physicallink can be modified, but the physical link cannot be deleted.

ping A method used to test whether a device in the IP network is reachable according to thesent ICMP Echo messages and received response messages.

ping test A test that is performed to send a data packet to the target IP address (a unique IP addresson the device on the network) to check whether the target host exists according to thedata packet of the same size returned from the target host.

plesiochronous digitalhierarchy (PDH)

A multiplexing scheme of bit stuffing and byte interleaving. It multiplexes the minimumrate 64 kit/s into rates of 2 Mbit/s, 34 Mbit/s, 140 Mbit/s, and 565 Mbit/s.

point-to-point service(P2P)

A service between two terminal users. In P2P services, senders and recipients areterminal users.

pointer An indicator whose value defines the frame offset of a virtual container with respect tothe frame reference of the transport entity on which this pointer is supported.

polarization A kind of electromagnetic wave, the direction of whose electric field vector is fixed orrotates regularly. Specifically, if the electric field vector of the electromagnetic wave isperpendicular to the plane of horizon, this electromagnetic wave is called verticallypolarized wave; if the electric field vector of the electromagnetic wave is parallel to theplane of horizon, this electromagnetic wave is called horizontal polarized wave; if thetip of the electric field vector, at a fixed point in space, describes a circle, thiselectromagnetic wave is called circularly polarized wave.

policy A set of rules that are applied when the conditions for triggering an event are met.

policy template A template that is used to define the calculation rules of a charging event, for example,rating, debiting and accumulating. A policy template may contain the parameters to beinstantiated. They can be used when the attributes of the condition judgment, calculationmethod, and action functions are carried out.

polling A mechanism for the NMS to query the agent status and other data on a regular basis.

port default VLAN ID(PVID)

A default VLAN ID of a port. It is allocated to a data frame if the data frame carries noVLAN tag when reaching the port.



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port priority The priority that is used when a port attaches tags to Layer 2 packets. Packets receivedon ports with higher priorities are forwarded preferentially.

power adjustment A method for dynamically and properly assigning power according to the real-time statusof a wireless network. When an AP runs under an AC for the first time, the AP uses itsmaximum transmit power. When getting reports from its neighbors (that is, other APsthat are detected by the AP and managed by the same AC), the AP determines to increaseor decrease its power according to the report conclusion.

power box A direct current power distribution box at the upper part of a cabinet, which suppliespower for the subracks in the cabinet.

power control A process in which the MS or BS uses certain rules to adjust and control the transmitpower according to the change in the channel condition and the power of the receivedsignal.

power distribution unit(PDU)

A unit that performs AC or DC power distribution.

power module The module that converts the external power input into the power supply for internaluse. Power modules are classified into AC power modules and DC power modules.

power off An operation that switches off devices during upgrade or expansion.

power on To start up a computer; to begin a cold boot procedure; to turn on the power

power spectrumdensity (PSD)

The power layout of random signals in the frequency domain.

printed circuit board(PCB)

A board used to mechanically support and electrically connect electronic componentsusing conductive pathways, tracks, or traces, etched from copper sheets laminated ontoa non-conductive substrate.

priority queuing (PQ) A queue scheduling algorithm based on the absolute priority. According to the PQalgorithm, services of higher priorities are ensured with greater bandwidth, lowerlatency, and less jitter. Packets of lower priorities must wait to be sent till all packets ofhigher priorities are sent. In this manner, services of higher priorities are processed earlierthan others.

private line A line, such as a subscriber cable and trunk cable, which are leased by thetelecommunication carrier and are used to meet the special user requirements.

protection path A path in a protection group that transports services when a fault occurs on the workingpath.

provider edge (PE) A device that is located in the backbone network of the MPLS VPN structure. A PE isresponsible for managing VPN users, establishing LSPs between PEs, and exchangingrouting information between sites of the same VPN. A PE performs the mapping andforwarding of packets between the private network and the public channel. A PE can bea UPE, an SPE, or an NPE.

pseudo random binarysequence (PRBS)

A sequence that is random in the sense that the value of each element is independent ofthe values of any of the other elements, similar to a real random sequence.

pseudo wire (PW) An emulated connection between two PEs for transmitting frames. The PW is establishedand maintained by PEs through signaling protocols. The status information of a PW ismaintained by the two end PEs of a PW.



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pseudo wire emulationedge-to-edge (PWE3)

An end-to-end Layer 2 transmission technology. It emulates the essential attributes of atelecommunication service such as ATM, FR or Ethernet in a packet switched network(PSN). PWE3 also emulates the essential attributes of low speed time divisionmultiplexing (TDM) circuit and SONET/SDH. The simulation approximates to the realsituation.

public switchedtelephone network(PSTN)

A telecommunications network established to perform telephone services for the publicsubscribers. Sometimes it is called POTS.

pulse A variation above or below a normal level and a given duration in electrical energy.

pulse code modulation(PCM)

A method of encoding information in a signal by changing the amplitude of pulses.Unlike pulse amplitude modulation (PAM), in which pulse amplitude can changecontinuously, pulse code modulation limits pulse amplitudes to several predefinedvalues. Because the signal is discrete, or digital, rather than analog, pulse codemodulation is more immune to noise than PAM.

Q

QA Q adaptation

QAM See quadrature amplitude modulation.

QPSK See quadrature phase shift keying.

QinQ A layer 2 tunnel protocol based on IEEE 802.1Q encapsulation. It add a public VLANtag to a frame with a private VLAN tag to allow the frame with double VLAN tags tobe transmitted over the service provider's backbone network based on the public VLANtag. This provides a layer 2 VPN tunnel for customers and enables transparenttransmission of packets over private VLANs.

QoS See quality of service.

quadrature amplitudemodulation (QAM)

Both an analog and a digital modulation scheme. It conveys two analog message signals,or two digital bit streams, by changing (modulating) the amplitudes of two carrier waves,using the amplitude-shift keying (ASK) digital modulation scheme or amplitudemodulation (AM) analog modulation scheme. These two waves, usually sinusoids, areout of phase with each other by 90° and are thus called quadrature carriers or quadraturecomponents — hence the name of the scheme.

quadrature phase shiftkeying (QPSK)

A modulation method of data transmission through the conversion or modulation andthe phase determination of the reference signals (carrier). It is also called the fourth periodor 4-phase PSK or 4-PSK. QPSK uses four dots in the star diagram. The four dots areevenly distributed on a circle. On these phases, each QPSK character can perform two-bit coding and display the codes in Gray code on graph with the minimum BER.

quality of service (QoS) A commonly-used performance indicator of a telecommunication system or channel.Depending on the specific system and service, it may relate to jitter, delay, packet lossratio, bit error ratio, and signal-to-noise ratio. It functions to measure the quality of thetransmission system and the effectiveness of the services, as well as the capability of aservice provider to meet the demands of users.

R

RADIUS See Remote Authentication Dial In User Service.



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RAI remote alarm indication

RDI remote defect indication

RED See random early detection.

REG See regenerator.

REI remote error indication

RF See radio frequency.

RIP See Routing Information Protocol.

RMEP remote maintenance association end point

RNC See radio network controller.

ROPA See remote optical pumping amplifier.

RP rendezvous point

RPR resilient packet ring

RS232 See Reference Standard 232.

RS422 The specification that defines the electrical characteristics of balanced voltage digitalinterface circuits. The interface can change to RS232 via the hardware jumper and othersare the same as RS232.

RSL See received signal level.

RSOH regenerator section overhead

RSSI See received signal strength indicator.

RST regenerator section termination

RSTP See Rapid Spanning Tree Protocol.

RTN radio transmission node

RTP See Real-Time Transport Protocol.

Rapid Spanning TreeProtocol (RSTP)

An evolution of the Spanning Tree Protocol (STP) that provides faster spanning treeconvergence after a topology change. The RSTP protocol is backward compatible withthe STP protocol.

Real-Time TransportProtocol (RTP)

A protocol defined by the IETF for transmitting audio and video streams. RTP is basedon UDP. In the RTP header, a time stamp is defined to ensure that audio and video datacan be transmitted and synchronized in real time. H.323 is based on RTP.

Reference Standard232 (RS232)

A standard that defines the electrical characteristics, timing, and meaning of signals, andthe physical size and pinout of connectors.

Remote AuthenticationDial In User Service(RADIUS)

A security service that authenticates and authorizes dial-up users and is a centralizedaccess control mechanism. RADIUS uses the User Datagram Protocol (UDP) as itstransmission protocol to ensure real-time quality. RADIUS also supports theretransmission and multi-server mechanisms to ensure good reliability.

RoHS restriction of the use of certain hazardous substances



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Routing InformationProtocol (RIP)

A simple routing protocol that is part of the TCP/IP protocol suite. It determines a routebased on the smallest hop count between the source and destination. RIP is a distancevector protocol that routinely broadcasts routing information to its neighboring routersand is known to waste bandwidth.

radio frequency (RF) A type of electric current in the wireless network using AC antennas to create anelectromagnetic field. It is the abbreviation of high-frequency AC electromagnetic wave.The AC with the frequency lower than 1 kHz is called low-frequency current. The ACwith frequency higher than 10 kHz is called high-frequency current. RF can be classifiedinto such high-frequency current.

radio networkcontroller (RNC)

A device in a radio network subsystem that is in charge of controlling the usage andintegrity of radio resources.

radio propagationmodel

An empirical mathematical formulation for the characterization of radio wavepropagation as a function of frequency, distance and other conditions. A single model isusually developed to predict the behavior of propagation for all similar links undersimilar constraints.

random early detection(RED)

A packet loss algorithm used in congestion avoidance. It discards the packet accordingto the specified higher limit and lower limit of a queue so that global TCP synchronizationresulting from traditional tail drop can be prevented.

rate limiting A traffic management technology used to limit the total rate of packet sending on aphysical interface or a Tunnel interface. Rate limiting is directly enabled on the interfaceto control the traffic passing the interface.

real-time variable bitrate (rt-VBR)

A parameter intended for real-time applications, such as compressed voice over IP(VoIP) and video conferencing. The rt-VBR is characterized by a peak cell rate (PCR),sustained cell rate (SCR), and maximum burst size (MBS). You can expect the sourcedevice to transmit in bursts and at a rate that varies with time.

reboot To start the system again. Programs or data will be reloaded to all boards.

received signal level(RSL)

The signal level at a receiver input terminal.

received signal strengthindicator (RSSI)

The received wide band power, including thermal noise and noise generated in thereceiver, within the bandwidth defined by the receiver pulse shaping filter, for TDDwithin a specified timeslot. The reference point for the measurement shall be the antenna

receiver sensitivity The minimum acceptable value of mean received power at point Rn (a reference pointat an input to a receiver optical connector) to achieve a 1x10-12 BER when the FEC isenabled.

recognition Consumer awareness of having seen or heard an advertising message.

reference clock A stable and high-precision autonomous clock that provides frequencies as a referencefor other clocks.

reflectance The ratio of the reflected optical power to the incident optical power.

regeneration The process of receiving and reconstructing a digital signal so that the amplitudes,waveforms and timing of its signal elements are constrained within specified limits.

regenerator (REG) A piece of equipment or device that regenerates electrical signals.



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relay An electronic control device that has a control system and a system to be controlled. Therelay of the telepresence system is used to control the power of telepresence equipmentand is controlled by the telepresence host.

remote opticalpumping amplifier(ROPA)

A remote optical amplifier subsystem designed for applications where power supply andmonitoring systems are unavailable. The ROPA subsystem is a power compensationsolution to the ultra-long distance long hop (LHP) transmission.

reservation An action that the charging module performs to freeze a subscriber's balance amount,free resources, credits, or quotas before the subscriber uses services. This action ensuresthat the subscriber has sufficient balance to pay for services.

resistance The ability to impede (resist) the flow of electric current. With the exception ofsuperconductors, all substances have a greater or lesser degree of resistance. Substanceswith very low resistance, such as metals, conduct electricity well and are calledconductors. Substances with very high resistance, such as glass and rubber, conductelectricity poorly and are called nonconductors or insulators.

resource sharing A physical resource belonging to two or more protection subnetworks.

response A message that is returned to the requester to notify the requester of the status of therequest packet.

robustness The ability of a system to maintain function even with changes in internal structure orexternal environment.

rollback A return to a previous condition through cancellation of a certain operation.

root alarm An alarm directly caused by anomaly events or faults in the network. Some lower-levelalarms always accompany a root alarm.

route The path that network traffic takes from its source to its destination. Routes can changedynamically.

router A device on the network layer that selects routes in the network. The router selects theoptimal route according to the destination address of the received packet through anetwork and forwards the packet to the next router. The last router is responsible forsending the packet to the destination host. Can be used to connect a LAN to a LAN, aWAN to a WAN, or a LAN to the Internet.

routing The determination of a path that a data unit (frame, packet, message) traverses fromsource to destination.

routing protocol A formula used by routers to determine the appropriate path onto which data should beforwarded.

rt-VBR See real-time variable bit rate.

S



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S1 byte A byte to transmit network synchronization status information. On an SDH network,each NE traces hop by hop to the same clock reference source through a specific clocksynchronization path, realizing synchronization on the entire network. If a clockreference source traced by an NE is missing, this NE will trace another clock referencesource of a lower level. To implement protection switching of clocks in the wholenetwork, the NE must learn about clock quality information of the clock reference sourceit traces. Therefore, ITU-T defines S1 byte to transmit network synchronization statusinformation. It uses the lower four bits of the multiplex section overhead S1 byte toindicate 16 types of synchronization quality grades. Auto protection switching of clocksin a synchronous network can be implemented using S1 byte and a proper switchingprotocol.

SAN storage area network

SAToP Structure-Agnostic Time Division Multiplexing over Packet

SC square connector

SCR sustainable cell rate

SD See signal degrade.

SD trigger flag A signal degrade trigger flag that determines whether to perform a switching when SDoccurs. The SD trigger flag can be set by using the network management system.

SD-SDI See standard definition-serial digital interface signal.

SDH See synchronous digital hierarchy.

SDP serious disturbance period

SDRAM See synchronous dynamic random access memory.

SELV safety extra-low voltage

SEMF synchronous equipment management function

SES severely errored second

SETS SDH equipment timing source

SF See signal fail.

SFP small form-factor pluggable

SFTP See Secure File Transfer Protocol.

SHDSL See single-pair high-speed digital subscriber line.

SMSR side mode suppression ratio

SNC subnetwork connection

SNCMP subnetwork connection multipath protection

SNCP subnetwork connection protection

SNCTP subnetwork connection tunnel protection

SNMP See Simple Network Management Protocol.

SNR See signal-to-noise ratio.

SOH section overhead



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SONET See synchronous optical network.

SPE See superstratum provider edge.

SSL See Secure Sockets Layer.

SSM See Synchronization Status Message.

SSMB synchronization status message byte

SSU synchronization supply unit

STD system target decoder

STP Spanning Tree Protocol

SVC switched virtual connection

Secure File TransferProtocol (SFTP)

A network protocol designed to provide secure file transfer over SSH.

Secure Sockets Layer(SSL)

A security protocol that works at a socket level. This layer exists between the TCP layerand the application layer to encrypt/decode data and authenticate concerned entities.

Simple NetworkManagement Protocol(SNMP)

A network management protocol of TCP/IP. It enables remote users to view and modifythe management information of a network element. This protocol ensures thetransmission of management information between any two points. The pollingmechanism is adopted to provide basic function sets. According to SNMP, agents, whichcan be hardware as well as software, can monitor the activities of various devices on thenetwork and report these activities to the network console workstation. Controlinformation about each device is maintained by a management information block.

Synchronization StatusMessage (SSM)

A message that carries the quality levels of timing signals on a synchronous timing link.SSM messages provide upstream clock information to nodes on an SDH network orsynchronization network.

security Protection of a computer system and its data from harm or loss. A major focus ofcomputer security, especially on systems accessed by many people or throughcommunication lines, is preventing system access by unauthorized individuals.

security service A service, provided by a layer of communicating open systems, which ensures adequatesecurity of the systems or of data transfer.

self-healing A function of establishing a replacement connection by network without the networkmanagement connection function. When a connection failure occurs, the replacementconnection is found by the network elements and rerouted depending on networkresources available at that time.

serial port An input/output location (channel) that sends and receives data to and from a computer'sCPU or a communications device one bit at a time. Serial ports are used for serial datacommunication and as interfaces with some peripheral devices, such as mice and printers.

service flow An MAC-layer-based unidirectional transmission service. It is used to transmit datapackets, and is characterized by a set of QoS parameters, such as latency, jitter, andthroughput.

service level The level of service quality of an evaluated party in a specified period, determined byan evaluating party.

service protection A measure that ensures that services can be received at the receive end.



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session A logical connection between two nodes on a network for the exchange of data. Itgenerally can apply to any link between any two data devices. A session is also usedsimply to describe the connection time.

shaping A process of delaying packets within a traffic stream to cause it to conform to specificdefined traffic profile.

signal degrade (SD) A signal indicating that associated data has degraded in the sense that a degraded defectcondition is active.

signal fail (SF) A signal indicating that associated data has failed in the sense that a near-end defectcondition (non-degrade defect) is active.

signal-to-noise ratio(SNR)

The ratio of the amplitude of the desired signal to the amplitude of noise signals at agiven point in time. SNR is expressed as 10 times the logarithm of the power ratio andis usually expressed in dB.

signaling The information exchange concerning the establishment and control of atelecommunication circuit and the management of the network.

single-ended switching A protection mechanism that takes switching action only at the affected end of theprotected entity in the case of a unidirectional failure.

single-pair high-speeddigital subscriber line(SHDSL)

A symmetric digital subscriber line technology developed from HDSL, SDSL, andHDSL2, which is defined in ITU-T G.991.2. The SHDSL port is connected to the userterminal through the plain telephone subscriber line and uses trellis coded pulseamplitude modulation (TC-PAM) technology to transmit high-speed data and providethe broadband access service.

single-polarizedantenna

An antenna intended to radiate or receive radio waves with only one specifiedpolarization.

slicing Dividing data into the information units proper for transmission.

smooth upgrade Process of upgrading the system files without service interruption

span The physical reach between two pieces of WDM equipment.

standard definition-serial digital interfacesignal (SD-SDI)

Standard definition video signal transported by serial digital interface.

static ARP A protocol that binds some IP addresses to a specified gateway. The packet of these IPaddresses must be forwarded through this gateway.

static route A route that cannot adapt to the change of network topology. Operators must configureit manually. When a network topology is simple, the network can work in the normalstate if only the static route is configured. It can improve network performance and ensurebandwidth for important applications. Its disadvantage is as follows: When a network isfaulty or the topology changes, the static route does not change automatically. It mustbe changed by the operators.

statistical multiplexing A multiplexing technique whereby information from multiple logical channels can betransmitted across a single physical channel. It dynamically allocates bandwidth only toactive input channels, to make better use of available bandwidth and allow more devicesto be connected than with other multiplexing techniques.



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steering A protection switching mode defined in ITU-T G.8132, which is applicable to packet-based T-MPLS ring networks and similar to SDH transoceanic multiplex sectionprotection (MSP). In this mode, the switching is triggered by the source and sink nodesof a service.

stress The force, or combination of forces, which produces a strain; force exerted in anydirection or manner between contiguous bodies, or parts of bodies, and taking specificnames according to its direction, or mode of action, as thrust or pressure, pull or tension,shear or tangential stress.

subnet A type of smaller networks that form a larger network according to a rule, for example,according to different districts. This facilitates the management of the large network.

subnet mask The technique used by the IP protocol to determine which network segment packets aredestined for. The subnet mask is a binary pattern that is stored in the device and is matchedwith the IP address.

superstratum provideredge (SPE)

Core devices that are located within a VPLS full-meshed network. The UPE devices thatare connected with the SPE devices are similar to the CE devices. The PWs set upbetween the UPE devices and the SPE devices serve as the ACs of the SPE devices. TheSPE devices must learn the MAC addresses of all the sites on UPE side and those of theUPE interfaces that are connected with the SPE. SPE is sometimes called NPE.

switching capacity The backplane bandwidth or switching bandwidth. The switching capacity is themaximum data that can be processed by the interface processor of a switch and the databus. The backplane bandwidth indicates the overall data switching capability of a switch,in Gbit/s.

switching priority A priority assigned to boards that share protection. If multiple boards that are sharingprotection fail, the services of the board with the highest priority are switched to theprotection board. If two or more boards have the same priority, the services of whicheverboard fails first are switched.

synchronous digitalhierarchy (SDH)

A transmission scheme that follows ITU-T G.707, G.708, and G.709. SDH defines thetransmission features of digital signals, such as frame structure, multiplexing mode,transmission rate level, and interface code. SDH is an important part of ISDN and B-ISDN.

synchronous dynamicrandom access memory(SDRAM)

A new type of DRAM that can run at much higher clock speeds than conventionalmemory. SDRAM actually synchronizes itself with the CPU's bus and is capable ofrunning at 100 MHz, about three times faster than conventional FPM RAM, and abouttwice as fast as EDO DRAM or BEDO DRAM. SDRAM is replacing EDO DRAM incomputers.

synchronous opticalnetwork (SONET)

A high-speed network that provides a standard interface for communications carriers toconnect networks based on fiber optical cable. SONET is designed to handle multipledata types (voice, video, and so on). It transmits at a base rate of 51.84 Mbit/s, butmultiples of this base rate go as high as 2.488 Gbit/s.

T

TCI tag control information

TCM tandem connection monitor

TCN topology change notification



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TCP See Transmission Control Protocol.

TCP/IP Transmission Control Protocol/Internet Protocol

TDC tunable dispersion compensator

TDM See time division multiplexing.

TE terminal equipment

TFTP See Trivial File Transfer Protocol.

TIM trace identifier mismatch

TLV See type-length-value.

TM See terminal multiplexer.

TMN See telecommunications management network.

TOD time of day

TPID tag protocol identifier

TPS See tributary protection switching.

TPS protection The equipment level protection that uses one standby tributary board to protect Ntributary boards. When a fault occurs on the working board, the SCC issues the switchingcommand, and the payload of the working board can be automatically switched over tothe specified protection board and the protection board takes over as the working board.After the fault is rectified, the service is automatically switched to the original board.

TSD trail signal degrade

TTI trail trace identifier

TTL See time to live.

TTSI See trail termination source identifier.

TU tributary unit

TU-LOP tributary unit loss of pointer

TUG tributary unit group

Tc committed rate measurement interval

Telnet A standard terminal emulation protocol in the TCP/IP protocol stack. Telnet allows usersto log in to remote systems and use resources as if they were connected to a local system.Telnet is defined in RFC 854.

Transmission ControlProtocol (TCP)

The protocol within TCP/IP that governs the breakup of data messages into packets tobe sent using Internet Protocol (IP), and the reassembly and verification of the completemessages from packets received by IP. A connection-oriented, reliable protocol (reliablein the sense of ensuring error-free delivery), TCP corresponds to the transport layer inthe ISO/OSI reference model.

Trivial File TransferProtocol (TFTP)

A small and simple alternative to FTP for transferring files. TFTP is intended forapplications that do not need complex interactions between the client and server. TFTPrestricts operations to simple file transfers and does not provide authentication.



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tail drop A congestion management mechanism, in which packets arrive later are discarded whenthe queue is full. This policy of discarding packets may result in network-widesynchronization due to the TCP slow startup mechanism.

tangent ring A concept borrowed from geometry. Two tangent rings have a common node betweenthem. The common node often leads to single-point failures.

telecommunicationsmanagement network(TMN)

A protocol model defined by ITU-T for managing open systems in a communicationsnetwork. TMN manages the planning, provisioning, installation, and OAM ofequipment, networks, and services.

terminal multiplexer(TM)

A device used at a network terminal either to multiplex multiple channels of low ratesignals into one channel of high rate signals, or to demultiplex one channel of high ratesignals into multiple channels of low rate signals.

threshold A limitation on an amount, scale, or level. Changes will occur when a threshold isreached.

threshold alarm The alarm occurs when the monitored value exceeds the threshold.

throughput The maximum transmission rate of the tested object (system, equipment, connection,service type) when no packet is discarded. Throughput can be measured with bandwidth.

throughput capability The data input/output capability of the data transmission interface.

time divisionmultiplexing (TDM)

A multiplexing technology. TDM divides the sampling cycle of a channel into time slots(TSn, n=0, 1, 2, 3…), and the sampling value codes of multiple signals engross time slotsin a certain order, forming multiple multiplexing digital signals to be transmitted overone channel.

time to live (TTL) A specified period of time for best-effort delivery systems to prevent packets fromlooping endlessly.

timer Symbolic representation for a timer object (for example, a timer object may have aprimitive designated as T-Start Request). Various MAC entities utilize timer entities thatprovide triggers for certain MAC state transitions.

timestamp The current time of an event that is recorded by a computer. By using mechanisms suchas the Network Time Protocol (NTP), a computer maintains accurate current time,calibrated to minute fractions of a second.

token bucket algorithm The token bucket is a container for tokens. The capacity of a token bucket is limited, andthe number of tokens determines the traffic rate of permitted packets. The token bucketpolices the traffic. Users place the tokens into the bucket regularly according to the presetrate. If the tokens in the bucket exceed the capacity, no tokens can be put in. Packets canbe forwarded when the bucket has tokens, otherwise they cannot be transferred till thereare new tokens in the bucket. This scheme adjusts the rate of packet input.

topology The configuration or layout of a network formed by the connections between devices ona local area network (LAN) or between two or more LANs.

topology discovery A technique to accurately determine the exact layout of a network using a fewassumptions about the network architecture and simple tools.

trTCM See two rate three color marker.

traceroute A program that prints the path to a destination. Traceroute sends a sequence of datagramswith the time-to-live (TTL) set to 1,2, and so on, and uses ICMP time exceeded messagesthat return to determine routers along the path.



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traffic The product of the number of calls made and received and the average duration of eachcall in a measurement period.

traffic classification A function that enables you to classify traffic into different classes with differentpriorities according to some criteria. Each class of traffic has a specified QoS in the entirenetwork. In this way, different traffic packets can be treated differently.

traffic policy A full set of QoS policies formed by association of traffic classification and QoS actions.

traffic shaping A way of controlling the network traffic from a computer to optimize or guarantee theperformance and minimize the delay. It actively adjusts the output speed of traffic in thescenario that the traffic matches network resources provided by the lower layer devices,avoiding packet loss and congestion.

traffic statistics An activity of measuring and collecting statistics of various data on devices andtelecommunications networks. With the statistics, operators can be aware of theoperating status, signaling, users, system resource usage of the devices or networks. Thestatistics also help the operators manage the device operating, locate problems, monitorand maintain the networks, and plan the networks.

trail managementfunction

A network level management function of the network management system. This functionenables you to configure end-to-end services, view graphic interface and visual routesof a trail, query detailed information of a trail, filter, search and locate a trail quickly,manage and maintain trails in a centralized manner, manage alarms and performancedata by trail, and print a trail report.

trail termination sourceidentifier (TTSI)

A TTSI uniquely identifies an LSP in the network. A TTSI is carried in the connectivityverification (CV) packet for checking the connectivity of a trail. If it matches the TTSIreceived by the sink point, the trail has no connectivity defect.

transaction Business between the customer and carrier, such as payment, and account adjustment.

transfer A process of transferring the account balance of an account to another account.

transit A packet is transmitted along an LSP consisting of a series of LSRs after the packet islabeled. The intermediate nodes are named transits.

transit node All the nodes except the master node on an RRPP ring.

transmission delay The period from the time when a site starts to transmit a data frame to the time when thesite finishes the data frame transmission. It consists of the transmission latency and theequipment forwarding latency.

transmit power control A technical mechanism used within some networking devices in order to prevent toomuch unwanted interference between different wireless networks.

transparenttransmission

A process during which the signaling protocol or data is not processed in the content butencapsulated in the format for the processing of the next phase.

tray A component that can be installed in a cabinet for holding chassis or other components.

tributary loopback A fault can be located for each service path by performing loopback to each path of thetributary board. There are three kinds of loopback modes: no loopback, outloop, andinloop.

tributary protectionswitching (TPS)

A function that uses a standby tributary processing board to protect N tributaryprocessing boards.

trunk Physical communications line between two offices. It transports media signals such asspeech, data and video signals.



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trunk link A link used to transport VLAN communication between two switches.

trunk port A switch port used to connect to other switches. The trunk port can connect to only thetrunk link. Only VLANs allowed to pass through a trunk port can be configured on thetrunk port.

tunnel A channel on the packet switching network that transmits service traffic between PEs.In VPN, a tunnel is an information transmission channel between two entities. The tunnelensures secure and transparent transmission of VPN information. In most cases, a tunnelis an MPLS tunnel.

tunnel ID A group of information, including the token, slot number of an outgoing interface, tunneltype, and location method.

twisted pair cable A type of cable that consists of two independently insulated wires twisted around oneanother for the purposes of canceling out electromagnetic interference which can causecrosstalk. The number of twists per meter makes up part of the specifications for a giventype of cable. The greater the number of twists is, the more crosstalk is reduced.

two rate three colormarker (trTCM)

An algorithm that meters an IP packet stream and marks its packets based on two rates,Peak Information Rate (PIR) and Committed Information Rate (CIR), and theirassociated burst sizes to be either green, yellow, or red. A packet is marked red if itexceeds the PIR. Otherwise it is marked either yellow or green depending on whether itexceeds or does not exceed the CIR.

type-length-value(TLV)

An encoding type that features high efficiency and expansibility. It is also called Code-Length-Value (CLV). T indicates that different types can be defined through differentvalues. L indicates the total length of the value field. V indicates the actual data of theTLV and is most important. TLV encoding features high expansibility. New TLVs canbe added to support new features, which is flexible in describing information loaded inpackets.

U

UART universal asynchronous receiver/transmitter

UAS unavailable second

UAT See unavailable time event.

UBR unspecified bit rate

UBR+ Unspecified Bit Rate Plus

UDP See User Datagram Protocol.

UNI See user-to-network interface.

UPC See usage parameter control.

UPE user-end provider edge

UPI user payload identifier

UPM uninterruptible power module

UPS uninterruptible power supply



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User DatagramProtocol (UDP)

A TCP/IP standard protocol that allows an application program on one device to send adatagram to an application program on another. UDP uses IP to deliver datagrams. UDPprovides application programs with the unreliable connectionless packet deliveryservice. That is, UDP messages may be lost, duplicated, delayed, or delivered out oforder. The destination device does not actively confirm whether the correct data packetis received.

unavailable time event(UAT)

An event that is reported when the monitored object generates 10 consecutive severelyerrored seconds.

unicast The process of sending data from a source to a single recipient.

unknown multicastpacket

A packet for which no forwarding entry is found in the multicast forwarding table.

uplink A transmission channel through which radio signals or other signals are transmitted tothe central office.

uplink tunnel GTP Tunnel from the Mobile Node to the SGSN.

upper limit A maximum consumption amount that a carrier sets for a subscriber in a bill cycle. Ifthe consumption amount if a subscriber exceeds the maximum consumption amount, theOCS system deducts only the maximum consumption amount from the account of thesubscriber.

upstream In an access network, the direction that is far from the subscriber end of the link.

upstream board A board that provides the upstream transmission function. Through an upstream board,services can be transmitted upstream to the upper-layer device.

usage parametercontrol (UPC)

During communications, UPC is implemented to monitor the actual traffic on each virtualcircuit that is input to the network. Once the specified parameter is exceeded, measureswill be taken to control. NPC is similar to UPC in function. The difference is that theincoming traffic monitoring function is divided into UPC and NPC according to theirpositions. UPC locates at the user/network interface, while NPC at the network interface.

user-to-networkinterface (UNI)

The interface between user equipment and private or public network equipment (forexample, ATM switches).

V

V-NNI virtual network-network interface

V-UNI See virtual user-network interface.

V.24 The physical layer interface specification between DTE and DCE defined by the ITU-T. It complies with EIA/TIA-232.

VAS See value-added service.

VB virtual bridge

VBR See variable bit rate.

VC trunk See virtual container trunk.

VCC See virtual channel connection.

VCCV virtual circuit connectivity verification

VCG See virtual concatenation group.



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VCI virtual channel identifier

VCTRUNK A virtual concatenation group applied in data service mapping, also called the internalport of a data service processing board.

VIP very important person

VLAN virtual local area network

VLAN mapping A technology that enables user packets to be transmitted over the public network bytranslating private VLAN tags into public VLAN tags. When user packets arrive at thedestination private network, VLAN mapping translates public VLAN tags back intoprivate VLAN tags. In this manner, user packets are correctly transmitted to thedestination.

VLAN mapping table One of the properties of the MST region, which describes mappings between VLANsand spanning tree instances.

VLAN stacking A technology that adds a VLAN tag to each incoming packet. The VLAN stackingtechnology implements transparent transmission of C-VLANs in the ISP network torealize the application of Layer 2 Virtual Private Network (VPN).

VP See virtual path.

VPI See virtual path identifier.

VPLS See virtual private LAN service.

VPN virtual private network

VRRP See Virtual Router Redundancy Protocol.

VSI virtual switch interface

Virtual RouterRedundancy Protocol(VRRP)

A protocol designed for multicast or broadcast LANs such as an Ethernet. A group ofrouters (including an active router and several backup routers) in a LAN is regarded asa virtual router, which is called a backup group. The virtual router has its own IP address.The host in the network communicates with other networks through this virtual router.If the active router in the backup group fails, one of the backup routers in this backupgroup becomes active and provides routing service for the host in the network.

value-added service(VAS)

A service provided by carriers and service providers (SPs) together for subscribers basedon voice, data, images, SMS messages, and so on. Communication network technologies,computer technologies, and Internet technologies are used to provide value-addedservices.

variable bit rate (VBR) One of the traffic classes used by ATM (Asynchronous Transfer Mode). Unlike apermanent CBR (Constant Bit Rate) channel, a VBR data stream varies in bandwidthand is better suited to non real time transfers than to real-time streams such as voice calls.

virtual channelconnection (VCC)

A VC logical trail that carries data between two end points in an ATM network. A point-to-multipoint VCC is a set of ATM virtual connections between two or multiple endpoints.

virtual circuit A channel or circuit established between two points on a data communications networkwith packet switching. Virtual circuits can be permanent virtual circuits (PVCs) orswitched virtual circuits (SVCs) .

virtual concatenationgroup (VCG)

A group of co-located member trail termination functions that are connected to the samevirtual concatenation link.



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virtual container trunk(VC trunk)

The logical path formed by some cascaded VCs.

virtual fiber The fiber that is created between different devices. A virtual fiber represents the opticalpath that bears SDH services in a WDM system.

virtual path (VP) A bundle of virtual channels, all of which are switched transparently across an ATMnetwork based on a common VPI.

virtual path identifier(VPI)

The field in the Asynchronous Transfer Mode (ATM) cell header that identifies to whichvirtual path the cell belongs.

virtual private LANservice (VPLS)

A type of point-to-multipoint L2VPN service provided over the public network. VPLSenables geographically isolated user sites to communicate with each other through theMAN/WAN as if they are on the same LAN.

virtual user-networkinterface (V-UNI)

A virtual user-network interface, works as an action point to perform serviceclassification and traffic control in HQoS.

voltage drop The voltage developed across a component or conductor by the flow of current throughthe resistance or impedance of that component or conductor.

W

WCDMA See Wideband Code Division Multiple Access.

WDM wavelength division multiplexing

WFQ See weighted fair queuing.

WLAN See wireless local area network.

WRED See weighted random early detection.

WRR weighted round robin

WTR See wait to restore.

Web LCT The local maintenance terminal of a transport network, which is located at the NEmanagement layer of the transport network.

Wideband CodeDivision MultipleAccess (WCDMA)

A standard defined by the ITU-T for the third-generation wireless technology derivedfrom the Code Division Multiple Access (CDMA) technology.

wait to restore (WTR) The number of minutes to wait before services are switched back to the working line.

wavelength The distance between successive peaks or troughs in a traveling wave, that is, the distanceover which a wave is transmitted within a vibration period.

weighted fair queuing(WFQ)

A fair queue scheduling algorithm based on bandwidth allocation weights. Thisscheduling algorithm allocates the total bandwidth of an interface to queues, accordingto their weights and schedules the queues cyclically. In this manner, packets of all priorityqueues can be scheduled.

weighted random earlydetection (WRED)

A packet loss algorithm used for congestion avoidance. It can prevent the global TCPsynchronization caused by traditional tail-drop. WRED is favorable for the high-prioritypacket when calculating the packet loss ratio.



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wireless local areanetwork (WLAN)

A hybrid of the computer network and the wireless communication technology. It useswireless multiple address channels as transmission media and carriers out data interactionthrough electromagnetic wave to implement the functions of the traditional LAN.

working path A path allocated to transport the normal traffic.

working service A specific service that is part of a protection group and is labeled working.

wrapping A protection switching mode defined in ITU-T G.8132, which is applicable to packet-based T-MPLS ring networks and similar to SDH two-fiber bidirectional multiplexsection protection (MSP). In this mode, the switching is triggered by the node that detectsa failure. For details, see ITU-T G.841.

X

X.21 ITU-T standard for serial communications over synchronous digital lines. It is mainlyused in Europe and Japan.

X.25 A data link layer protocol. It defines the communication in the Public Data Network(PDN) between a host and a remote terminal.

Y

Y.1731 The OAM protocol introduced by the ITU-T. Besides the contents defined byIEEE802.1ag, ITU-T Recommendation Y.173 also defines the following combinedOAM messages: Alarm Indication Signal (AIS), Remote Defect Indication (RDI),Locked Signal (LCK), Test Signal, Automatic Protection Switching (APS), MaintenanceCommunication Channel (MCC), Experimental (EXP), and Vendor Specific (VSP) forfault management and performance monitoring, such as frame loss measurement (LM),and delay measurement (DM).



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Documents

OSN 550 V100R007C10 Product Description