3G Radio Access Network 3G Radio Access Network
IMS
MNP
CBS : Cell Broadcast Service
CBC : Cell Broadcast Center
MNP : Mobile Number Portability
SRR : Service Routing Register
SCN : Switching Core Network
PCN : Packet Core Network
IMS : IP Multimedia Subsystem
CPS : Call Processing Server
IMR : IP Multimedia Register
Nokia IPA2800 Packet Platform
Nokia IPA2800 Packet Platform
IPA2800 Packet Platform is targeted primarily to those carrier grade applications in which the emphasis is on the effective user plane manipulations in both IP and ATM domains
Typical application areas are in network elements like WCDMA Radio Network Controller and Gateways
between ATM, IP and TDM networks
* © Nokia Siemens Networks June 2007
IPA 2800 vs. DX200
There exists many differences between the IPA2800 and the DX200, but the objective has been to continue to use as many of the features found in the DX200 as possible.
* © Nokia Siemens Networks June 2007
IPA 2800 vs. DX200: Hardware
Switching : The use of ATM switching, instead of TDM
Network Interfaces : A variety of network interfaces types are used and network inter-working is supported
Mechanics : A new mechanics concept and new dimensioning is used in IPA
Plug-in units : All plug-in units are different in IPA2800 platform and DX 200 platform.
System internal communication :
Hardware Management System : replaces
Compact network elements
IPA 2800 vs. DX200: Computing Platform
Missing DX 200 features in IPA2800
Serial channel terminals (i.e. no VDU- or LPT-devices)
Open reel tape units (MTU) and DAT are replaced with Optical Disks
F5 diskette format is replaced by MS DOS format
D-channel protocols (24 B+D, Abis)
X.25 interfaces
Messaging)
IPA2800 RNC Hardware Platform
EC216 Cabinet (taller)
CPD120 and PD30 power units
FTRA-B cooling unit
Fan Tray, FTR
Each subrack in the exchange is provided with a dedicated Fan Tray (FTR) cooling unit, since forced cooling is needed in the cabinets due to the high thermal density. The FTR has eight separate fans with an aggregate capacity sufficient to ensure redundancy for one of the fans in case of a failure, along with air deflectors, which help to spread the cool air evenly through the subrack.
The FTRs are controlled by the PD20 power supply plug-in units on the basis of messages sent by the OMU. The OMU, in turn, is supported by the Hardware Management System, which collects alarms from the FTRs and controls the temperature inside each plug-in unit. In case high temperatures are detected, the OMU will automatically instruct the PD20s (via the HMS bus) to increase the rotation speed of the fans so that the temperature can be restored to an appropriate level.
Like the subracks, the FTRs are fixed to the cabinets by attaching them to the mounting flanges. In case of a severe fault, an FTR can be hot-swapped without any need for plug-in unit switch-over procedures.
A new FTRA Fan Tray is based on FTR1 Fan Tray unit. New design is needed to meet NEBS requirements. The most important requirements are: sound pressure, fire resistance and heat dissipation from one plug-in unit slot.
* © Nokia Siemens Networks June 2007
Cabinents & Subracks
Cabinent info
Radio Network Controller (RNC)
Switching and multiplexing
NEMU
RNAC
RNBC
Cabinet height 1800 mm
Width & depth 600 mm
The mechanical structure is hierarchical, based on : Plug-in-units, Subracks and Cabinets
The PIU location is defined in terms of three location components:
Rack number – Subrack number – PPA number
Cabinet contains 4 subracks, 4 fan trays, and power distribution equipment
Height 300 mm
* © Nokia Siemens Networks June 2007
Functional Unit Categories in RNC
Network Interface Units
OMU, RRMU, RSMU, GTPU, ICSU and NEMU
Signal Processing Units
TBU, EHU
Redundancy Principles
Duplication (2N)
one spare unit designated for one active unit software in the unit pair is kept synchronized (hot-standby) -> fast switchover
Replacement (N+1)
one or more units designated to be spare units for a group allocating resources to a unit defines it as active, not allocating resources defines to be spare unit can replace any active unit in the group -> slower switchover, requires warming (cold-standby) users responsibility to change the working state of the unit to reflect the resource allocation situation and to leave at least one spare unit
Load sharing (SN+)
no spare units, group acts as a resource pool number of units selected so that there is overcapacity, if a few units are disabled, the whole group can still perform its functions
No redundancy
2N duplicated units
N+1 one spare unit (to take over the load of a faulty unit)
SN+ one unit´s extra capacity (workload shared between all units)
n no redundant
Switching Fabric Unit (1/2)
Operates according to a non-blocking connection principle
Supports both point-to-point and point-to-multipoint connection topologies
Handles various ATM service categories.
Redundancy: 2N
* © Nokia Siemens Networks June 2007
Multiplexer Unit
Purpose:
Enables connection of the low-to-medium bit-rate signal processing units and computer units, as well as low-bit-rate network interface units, to the ATM switch fabric
Performs the multiplexing and demultiplexing of ATM cells
ATM layer management and processing functions such as header translation, UPC/NPC parameter control, OAM functions, traffic management
Redundancy: 2N
ATM Multiplexer Plug-in Unit 622 Mbit/s
* © Nokia Siemens Networks June 2007
SFU
MXU
CU
NIU
CU
NIU
SPU
Multiplexing
Traffic from units with lower capacities are multiplexed in order to utilize switching fabric interface capacity (622 Mbit/s) effectively
Up to 18 tributary units can be connected to one MXU
CU
NIU
CU
NIU
SPU
MXU
CU
NIU
CU
NIU
SPU
MXU
ATM Multiplexing provides the means to connect tributary units to the MXU. (Tributary unit = any Plug-in-unit connected to MXU)
Facilitates the multiplexing of traffic sources with bit rates between 2 Mbit/s and 155 Mbit/s into an aggregate 622 Mbit/s bit rate, target is to utilize switch fabric port capacity more effectively
Redundant ATM multiplexing unit (MXU) is supported
Maximum capacity of tributary unit 155 Mbit/s
Maximum number of tributary units connected to multiplexing unit 18
No traffic concentration supported
Purpose:
The A2SU is an AAL Type 2 CPS minipacket switching unit, which is used in association with the Multiplexing Unit (MXU)
Guarantee bandwidth efficient and limits the transfer delay and of AAL type 2 connection
Redundancy: SN+
(CDSP)
The Management and Control Computer Unit category comprises the following
functional units:
RSMU ( Resource and Switch Management Unit )
GTPU ( GPRS Tunneling Protocol Unit )
* © Nokia Siemens Networks June 2007
Operational and Management Unit
Handles all the RNC's crucial maintenance functions, such as hardware configuration management, Hardware Management System (HMS) supervision, and the associated centralised recovery functions.
Activates appropriate recovery and diagnostics procedures
Serves as an interface between the NEMU and the other units
Houses the databases containing entire system software, alarms and radio network configuration.
Redundancy: 2N
* © Nokia Siemens Networks June 2007
OMU's storage devices
RNAC
New plug-in unit HDS-B, consist of two Hard Disk Drive (HDD): One for OMU and another for NEMU
73 GB formatted storage capacity/disk
Redundancy type : 2N
Network Element Management Unit
Firewall functionality for protecting LAN/Ethernet connections to environment
O&M functionalities which are not handled by other computer unit
Post-processing of Fault management and Performance Data
Peripheral device control
NEMU
GUI
OSS
Post-processing support
GUI
Navigation
Radio Resource Management Unit
Controls signaling connections between RNC and CN, and between RNCs.
Maintains centralized information, state changes of subsystems, UL scrambling codes.
Paging message grouping and routing to the RRC protocol according to the centralized connection information.
Takes care of resource releasing due the fault situations of ICSU units
(e.g. forced switchover, reset, overload)
Redundancy: 2N
* © Nokia Siemens Networks June 2007
Interface Control and Signalling Unit
Purpose:
Signalling protocols to Iu, Iub, Iur and Iu-BC interfaces for
- NBAP, RNSAP, RANAP, SABP signalling
- ALCAP (Q.2630.1) signalling
- RRC signalling
Termination of the UNI-SAAL (Iub), NNI-SAAL/MTP-3 (Iur and Iu) and TCP/IP (Iu-BC) signalling links
Monitoring and recovery of the signalling links
Radio resource management functions
* © Nokia Siemens Networks June 2007
Resource and Switch Management Unit
Purpose:
Establishes connections for calls according to requests from the signalling computer units (ICSUs).
Handles DSP resource management.
Allocation of the DSPs and associated computer resources to different tasks, such as macrodiversity combining and data traffic functions.
ATM switching management functions:
Establishment of both internal and external connections via the SFU
Management and control of the SFU, A2SU and MXU.
Transmission resource management.
* © Nokia Siemens Networks June 2007
GPRS Tunnelling Protocol Unit
UDP/IP (User Datagram Protocol / Internet Protocol) protocols termination
IP and GTP protocol processing
Redundancy: SN+
* © Nokia Siemens Networks June 2007
Signal Processing Units
Signal Processing Units
* © Nokia Siemens Networks June 2007
Data and Macro-Diversity Combining Unit
Purpose:
WCDMA L1 functions, including macro-diversity combining (MDC) and outer loop power control.
RLC and MAC functions
GTP termination
Network Element Interface Units
These units serve as the trunk network interfaces of the exchange.
The category comprises the following units:
Network Interface Unit: (ATM )
IMA Group
Several T1/E1/JT1s can be used for one IMA group
IMA Group
A number of PETs forms a new physical interface entity to increase capacity by using PDH ET’s
Iub: max 8xT1/E1/JT1
Iur: max 16xT1/E1/JT1
* © Nokia Siemens Networks June 2007
SONET APS Automatic Protection Switching
The SONET (Synchronous Optical NETwork) APS provides at the multiplexer section level protection for transmission link (ANSI, Bellcore standards).
When primary transmission link fails the APS protocol moves traffic to secondary transmission link automatically.
The implemented Sonet APS protocol Linear APS 1:1.
SETs of the protected interface pair can be located in different NIUs when protection is used i.e. 2N redundant units are supported.
* © Nokia Siemens Networks June 2007
Timing, HMS & Power Supply
The clock distribution and Hardware Management Subsystems in the exchange
use the same two types of plug-in units, namely:
• TSS3 ( Timing and Synchronization, SDH Stratum 3/TDM )
• TBUF ( Timing and Buffer )
The Power Distribution Subsystem in the exchange uses two types of plug-in
units, namely:
• CDP120 ( Cabinet Power Distributor 120 A )
* © Nokia Siemens Networks June 2007
Power Distribution System
Purpose:
Distributes the -48 V/-60 V power from the rectifiers or batteries to the equipment inside the RNC cabinets
Consists of:
PD20/30 plug-in units in the subracks
PD20/30 controls the cooling equipment of its own subrack on the basis of messages sent by the OMU
Redundancy: None
* © Nokia Siemens Networks June 2007
Timing and Synchronization System
Purpose:
Receives an input timing signal from upper network level, and adjusts its local oscillator to long time mean value and delivers this synchronised timing signal as system timing to all plug-in units in the same subrack and TBUF
Operates in plesiochronous mode, if all synchronisation are lost
Collect alarms from the PIUs in the same subrack and transfer them to HMS master (OMU)
3 synchronisation inputs from line interface card
Redundancy: 2N
* © Nokia Siemens Networks June 2007
Timing Buffer
The TBUF unit is a clock buffer
Distributes the synchronisation signals generated by the TSS3s to plug-in units not directly fed by the TSS3s.
Collects the alarms from the PIUS in the same subrack and transfers them further to the HMS master net, which brings the alarms to the appropriate OMU.
Redundancy: 2N
Timing Bus