ITU-TSG15 ITU-T Standardization Seminar – Madrid, 12-13 December 2002 Optical and xDSL Access work in ITU-T Study Group 15 Presented by: Simão Ferraz de

ITU-TITU-TSG15SG15

ITU-T Standardization Seminar – Madrid, 12-13 December 2002

Optical and xDSL Access work in ITU-T Study Group 15

Presented by:Simão Ferraz de Campos Neto

Counsellor – ITU-T Study Group 16Multimedia Services, Systems and

Terminals

ITU-TITU-TSG15SG15


Contents

o About ITU-T SG 15

o Optical Access

o xDSL Access

o Other access technologies

ITU-TITU-TSG15SG15


About Study Group 15

ITU-TITU-TSG15SG15


ITU-T Study Group 15

Responsible for studies relating to:o optical and other transport networks,

systems and equipment including transmission layer related standards for access, metropolitan and long haul sections of communication networks

Lead Study Group on o Access Network Transport (ANT)o Optical Technology

(www.itu.int/ITU-T/studygroups/com15)

Responsible for the development of Recs. in the G-series that support xDSL and optical

accesses.

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Many a type of access

F.O.

Copper or F.O.

Copper

Broadcast

SAT

Longhaul

Distribution Network

Access Network

Cable

Home Network

UNI SNI

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ITU-T Study Group 15 Structurehttp://www.itu.int/ITU-T/studygroups/com15/index.asp

Study Group 15Optical and other transport networks

Peter Wery

Working Party 3OTN Structure

Stephen Trowbridge

Working Party 4OTN Technology

Gastone Bonaventura

ITU-TSBCounsellorPaolo Rosa

Working Party 2Network Signal Proc.

Yushi Naito

Working Party 1Network Access

Andrew Nunn

Working Party 5Projects and Promotion

Haruo Okamura

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Overview of Access Technologies

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Typical Access Network Construction

Central Office

(Exchange)

Feeder Network

Street Cabinet

Distribution Network

Overhead Feed

Underground Feed

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Access technological evolution

Year9.6 kbit/s28.8 kbit/s

56.6 kbit/s

128 kbit/s

2 Mbit/s

640 kbit/s

8 Mbit/s

25 Mbit/s

50 Mbit/s

1989 1997 2000

Analog modems

ISDN

HDSL/ADSL

VDSL

OPTICALACCESS 622 Mbit/s

G-PON

2003

ITU-TITU-TSG15SG15

ITU-T Standardization Seminar – Madrid, 12-13 December 2002Source Siemens

There will never be enough! The bandwidth demand will continue to grow.Fiber to the home will be necessary sooner or later.

ISDN

100

1k

10k

100k

1M

10M

100M

1G

1980 1990 2000 2010 2020

Year

Bit

rat

e pe

r us

er (

bit/

s)

PSTN / Modem

ADSL

SDSL

FTTH

double in 18 mon .

double in 24 mon .

N.B. The technology bars show

the introduction, not the end of

the technology

VDSL, FTTCab

Capacity, technologies & availability

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Optical access network architecture (G.983.1)

ONU

ONU

ONU

O L T

NT

NT

Fibre

Fibre

Fibre

Copper

CopperHOME

Access network

SNI

FTTB/C

FTTCab

FTTH

Optical Distribution Network

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Characteristics of different access technologies

Technology

Definition Bandwidth Advantages Disadvantages

ADSLAsymmetric Digital Subscriber Line

Transmission of voice and data over copper

Up to 8 Mbit/s downstream

Up to 1.5 Mbit/s upstream

Makes full use of existing copper Ideal for web-browsing Good platform for voice

Limited video capability Distance limitation Limited upstream bandwidth

VDSLVery High Rate Digital Subscriber Line

Transmission of video, voice and data over copper

Up to 52 Mbit/s downstream Up to 26 Mbit/s symmetrical

Supports broadcast video, Video-on-demand, Internet TV, and interactive TV Offers always-on network for voice, video, and data

Requires short distance Non-standard products and technology Limited scalability

µwave multipoint fixed services

Microwave transmission of video and dataPoint-to-point or point-to-multipoint

Up to 1 Gbit/s downstream and downstream

Fast time-to-market Point-to-multipoint cells have limited geographical area

Needs line of sight to complete transmission

HFCHybrid Fibre/Coax

Transmission of video, voice, and data over coaxial and fibre cable

10 to 42 Mbit/s downstream

2 Mbit/s upstream

Supports broadcast video, Video-on-demand, Internet TV, and interactive TV Offers always-on network for voice, video, and data

Voice requires special engineering Difficult to guarantee speed High cost of upgrades and build-outs

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How hungry an application?

2

1

0.5

Up

stre

am M

bit

/s

0.5 1 2 84 Downstream Mbit/s

Business TV

Voice

e-commerce

Video conference

Internet access

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Optical Access

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Optical Systems for Access NetworksMarket & Business Drivers (1)

o Getting PSTN, data and cable TV together on one system at competitive prices

o Fibre To The Home (FTTH) is the next step for many operators

o The major change is driven by the explosive growth of the Internet usage

o Public and private networks evolve from multiple overlay networks to a unified network platform able to carry multiple applications

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Optical Systems for Access NetworksMarket & Business Drivers (2)

o IP routers and ATM switches are providing higher and higher speed optical interfaces

o Major carriers are realizing that services at STM-16 (2.5 Gbit/s) optical pipes may well represent more than 50% of the bulk bandwidth entering networks in the near future

o The new high speed data requirements are requiring a new category of Wavelength Services

o These new services will require new networking functions (performance monitoring, fault localization, network restoration, etc)

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Key aspects for optical technologies

o IP over optical, business and market aspectso Switched optical networkso Optics in access and metropolitan networkso Optical interfaceso Optical/IP network OAM and protection and

restorationo WDM and C&D-WDMo Signalling and routingo Optical fibres, cables and componentso Optical network managemento Optical switching equipmento Network performance (IP/Optical)o Optical network clients and serviceso Services and network evaluation

Making fully-optical networks viable

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• Optical Transport Network (OTN) structure – Automatic Switched Optical Network (ASON)– Architecture and interfaces for the OTN– Optical Cross-Connect and Switch functions– Network management and control

• OTN technology (terrestrial and submarine)– Coarse and Dense WDM, 40 Gbit/s signal channels– Optical components & amplifiers (e.g. tunable filters)– Fiber characteristics, more channels/fiber– Transmission technology (Soliton/RZ), long reach

OTN Structure and Technology

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TDM Systems@ 1310 nm

TDM systems @ 1550 nm

DWDM Systems

CWDM Systems

Fibre G.652(zero-dispersion @ 1310 nm) [1984]

[1988]

[1996]

[2000]

Fibre G.653(zero-dispersion @ 1550 nm)

Fibre G.655(low dispersion @ 1550 nm)

Fibre G.652.C(zero dispersion @ 1310 nm)

(flat attenuation lossfrom 1260 to 1625 nm)

TDM Systems @ 850 / 1310 nm

Fibre G.651multimode [1980]

Evolution of Standardization – Fibres

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Recs. Bit rate Content Date

G.955 140 Mbit/s Single channelPDHLong. Compat.

1984

G.957 STM-16 Single channelSDHtransv. Compat.

1998

G.691 STM-4 up toSTM-256

Single channelTransv compat.Terminal OAs

1994-2000

Evolution of Standardization – Systems (1)

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G.692 622 Mbit/s – 10 Gbit/s(STM-4 to STM-16)

WDM 4 to 32 chLong. Compat.Line amplifiersmono/bidirect.

1996 / 1998

G.959.1 2.5 and 10 Gbit/s

Up to 16 channels WDM

Pre-OTNSingle /WDMTransv Compat.Term. OAsId Interfaces

2000

G.693 10 – 40 Gbit/s(STM-64 to STM-256)

Single channelTransv. Compat.Intra office

2001

G.694.1G.694.2

≥ 80 Ch/10 Gbit/sUp to 18 Ch/2.5 Gbit/s

Dense WDM Coarse WDM

2002

Evolution of Standardization – Systems (2)

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OTN Standardization Work Plan

Global Optical Transport Network Supporting Today's and Future Services

OTNIrDI

OTNIaDI

Carrier Domain A Carrier Domain B

SDHSTM-N

USER NE USER

NE

OTNIaDI

OTNIaDI

OTNIrDI

OTNNE

OTNNE

OTNNE

User/carrier may originate/terminate the OTN framing for any OTN framing for any digital payloaddigital payload(IP, ATM, SDH,,,)(IP, ATM, SDH,,,)

IaDI = Intra-Domain InterfaceIrDI = Inter-Domain InterfaceNE = Network Element Interfaces:For single/multichannels with performance monitoring

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o G.957:• only with electrical regenerators• short distances, small capacities

o G.691:• Uses optical amplifiers only as Booster or Pre-amplifiers• transversal compatibility• bit rates up to STM-64 (10 Gbit/s)• target distances (up to 160 km) based on 11dB/40km at 1550 nm and

11dB/20 km at 1310 nm

WAVELENGHT 1310 1550 1550 1310 1550 1550 1310 1550 1550 1550 1550

Fibre Type G.652 G.652 G.653 G.652 G.652 G.653 G.652 G.652 G.653 G.652 G.653

Target Dist. (Km) 20 40 40 40 80 80 80 120 120 160 160

STM-1 - - - - -

STM-4 G.957 V-4.1 V-4.2 V-4.3 U-4.2 U-4.3

STM-16 V-16.1 V-16.2 V-16.3 U-16.2 U-16.3

STM-64 S-64.1 S-64.2 S-64.3 L-64.1 L-64.2 L-64.3 V-64.1 V-64.2 V-64.3 - -

Single channel systems (G.957 and G.691)

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Optical systems for access networks Broadband PON: G.983.x-series Recs.

o Passive Optical Network up to 622 Mbit/s symmetrical / asymmetrical

o Supports wide range of narrow- & broadband services like:• PSTN / ISDN / Multiple Line• Data / LAN interconnection / High speed Internet (~100

Mbit/s)• Cable TV / Video on demand (up to 400 TV channels on

single wavelength)• Videoconferencing

o Independent from bit rates, signal formats (digital or analogue, SONET/SDH etc.) and protocols (IP, Ethernet, ATM etc.)

o Need to deploy only the equipment needed for specific services needs to be added at the ends of the network as needed to add new services to existing customers or to add new customers.

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Optical systems for access networksG.984.x -series Recs (G-PON) – (01-2003)

o Gbit/s capable PON systemso Symmetrical/Asymmetricalo 1.244 and 2.488 Gbit/s downstreamo 155 Mbit/s up to 2.488 Gbit/s upstreamo Business and residential userso Convenient support of IP and Ethernet o Same wavelength plan and full-

network design principles as in G.983.x-series (B-PON)

New!

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Automatic Switched Optical Network (ASON) G.8080

o Architecture components and interactions between control plane, management plane and transport plane for switched wavelength & sub-wavelength connection services.

o Functions:• Facilitate fast & efficient configuration of connections within a

transport layer network• Re-configure connections to maintain calls• Restoring functionCost-effective and survivable architectures

o Adds dynamic capability to new optical networks or already established SDH networks

o Fast turn-up and rapid provisioning; as well as wavelength-on-demand services to increase capacity and flexibility

o Reduced operations cost: more accurate inventory & topology information, resource optimization and automated processes

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G.8080 Control Plane and Optical Layer

OCC OCCOCC

OCCASON Control PlaneASON Control Plane

Optical LayerOptical LayerOS

OS OS OSλs, STM-N granularity

OS = Optical SwitchOCC = Optical Connection Controller

Clients, e.g.

IP, ATM, TDM

Clients, e.g.

IP, ATM, TDM

NNI

CCIUNI

IrDI NNI

IrDI

UNI = User Network I/FNNI = ASON control Node-Node I/F

Optical Layer topology, status, control

CCI = Connection Control I/FIrDI = Inter Domain I/F

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Coperation:ITU-TIECETSI

Competition:IECIETFIEEE

Fora, Consortia, etc

Relationships:– ATM Forum [traffic and networks management]– DSL Forum [Access network]– TM Forum [network management]– ATIS T1 [Access, SDH, OTN]– IETF [optical transport network]– IEEE [Ethernet, optical interfaces]– TIA [optical networks and technology]– OIF [optical networks and technology]

SDOs cooperating with ITU-T

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• Ethernet – PON combination for high bit rate• End-to-end wavelength services• OTN management Information Model (Protocol

neutral and specific)• Terabyte/s in metropolitan and long haul

transport– Optical Internet– Dense & Coarse WDM, PONs

• Multi-Megabit/s and Gigabit/s network access– Internet– TV distribution and interactive

Work in progress

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xDSL Access

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xDSL Market & Business Drivers

o xDSL technology allows the provision of high-speed Internet access and other broadband services over existing copper access lines

o Incumbent operators need to exploit their large installed base of copper access lines for broadband deployment

o Competing operators can exploit incumbent operators access lines via ‘unbundling’ agreements

o Competition:• Digital Cable / Cable Modem• Bi-directional Satellite

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Typical components of an xDSL system

audio/video/data

POTSSplitter

xDT

= SN = Service Node xDSL

xDT xDSL TransceiverDTU-R = Transceiver Unit- RemoteDTU-C = xDSL Transceiver Unit- Central office

U-R

T

CUSTOMER PREMISES CENTRAL OFFICE

POTSSplitter

xDT

U-C

SNI

• PSTN/ISDNSN

• B-ISDN SN• Non-ATM based SN(e.g. - video server - IP router)

(Subscriber line)

xDTU-R xDTU-C

ADSL

ADSL lite

HDSL

SHDSL

VDSL

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Typical rates & loop lengths for xDSL

Technology

Up-stream

(kbit/s)

Down-stream

(kbit/s)

Loop length

(km)

HDSL

1 x 2320 2 x 1168 2/3x 784

1 x 2320 2 x 1168 2/3x 784

3

ADSL.dmt

640

(512)

>6144 (3000)

2.7

(4-6)

ADSL.lite

512

1536

5.4

SHDSL

192 2 312

192 2 312

5 2

VDSL

1 600 3 200 6 400

13 000 26 000 52 000

1 500 m

300 m

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o G.995.1 – Overview of Digital Subscriber Line (DSL) Recommendations

o G.991.1 (HDSL) – High-bit rate Digital Subscriber Line (HDSL) transmission system on metallic local lines

o G.991.2 (G.SHDSL) – Single-pair High bit rate speed Digital Subscriber Line

o G.993.1 (G.VDSL) – Very high bit-rate Digital Subscriber Line

o G.994.1, G.996.1 and G.997.1 for tests, management and handshake

o ADSL next slide

ITU-T Recommendations on DSL

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o G.992.1 (G.DMT) – Asymmetrical Digital Subscriber Line (ADSL) Transceivers

o G.992.2 (G.LITE) – Splitterless Asymmetrical Digital Subscriber Line (ADSL) Transceivers

o G.992.3 – Asymmetric digital subscriber line transceivers - 2 (ADSL2.DMT)

o G.992.4 – Splitterless asymmetric digital subscriber line transceivers - 2 (ADSL2.LITE)

ITU-T Recommendations on ADSL

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ADSL versus ADSL2(G.992.1 x G.992.3)

o 2nd generation of ADSL with improvements on: • data rate versus loop reach performance• loop diagnostics• deployment from remote cabinets• spectrum control• power control • robustness against loop impairments and RFI• operations and maintenance

o Improved application support for an all digital mode of operation and voice over ADSL operation;

o Fallback compatibility (?) (if manufacturer opts)

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ADSL+ (01/2003)

o G.adslplus G.992.5?

o A delta regarding ADSL2 (G.992.3) DMTo Performanceo Compatibility (but requires ADSL2)o Data rate on long distanceso ADSL+ doubles the bandwidth and

therefore can significantly increase data rates on short loops (extra bandwidth can only be used if the loop attenuation is low enough up to ~ 2.5–3 km).

Soon-to-be!

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Other Access Technologies

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Home Phone-line Networking Market & Business Drivers

o Redeployment of existing infrastructure facilitates penetration

o Potentially a large market as many homes now have more than one computer and need to share an internet connection and printer etc.

o Network Operators see this as a stimulus for broadband deployment

o Competition: • Powerline networking• WiFi (IEEE 802.11x)

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Relevant Recommendations

o Done: G.989.1/G.989.2 – Home Phoneline Networking Transceivers

o In progress: G.pnt.if – Phone-line Networking - Isolation Filter

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Things in progress in SG15

o Network access• Home networking (data on in-premises wiring)• Refinements & enhancements xDSL • Web-based ANT standardization plan

o Optical Transport Network (OTN)o x-WDM and 40Gbit/s signal channels

• Optical Cross-Connect and Switch• Fiber characteristics, more channels/fiber• Transmission technology (Soliton/RZ)• Network Node Interface for OTN

o Continue as Lead Study Group on • Access Network Transport• Optical Technology

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Thank you for your attention!For further contact, please feel free to contact:

Presenter: Simão Ferraz de Campos [email protected]

Tel: +41-22-730-6805 Fax: +41-22-730-4345

Counsellor for SG 15: Paolo [email protected]

Tel: +41-22-730-5235 Fax: +41-22-730-4345

http://www.itu.int/ITU-T

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SupplementalSlides

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Q.2/15 - Optical systems for access networks

Recommendations

o G.983.1 + Amendment 1 - High speed optical access systems based on Passive Optical Network (PON) techniques

o G.983.2 - ONT Management and Control Interface specification for ATM PON

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Recommendations (continued)

o G.983.3 - A broadband optical access system with increased service capability by wavelength allocation

o G.983.4 - A broadband optical access system with increased service capability using Dynamic Bandwidth Assignment

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o G.983.5 - A broadband optical access system with enhanced survivability

o G.983.7 - ONT Management and Control Interface specification for Dynamic Bandwidth Assignment

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G.983.1 + Amendment 1 - High speed optical access systems based on Passive Optical Network (PON)

techniques

o ATM-PONo 155.520/155.520 Mbit/s, 622.080/155.520

Mbit/s or 622.080/622.080 Mbit/s downstream/upstream

o Single or two fibre working o Maximum range of at least 20 Km

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G.983.3 - A broadband optical access system with increased service

capability by wavelength allocation

o Defines new wavelength allocations to distribute ATM-PON signals and additional service signals simultaneously

o Allows distribution of video broadcast services or data services without disturbing basic ATM-PON system

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Current/future work

o Enhancement of G.983.2 to support survivability (G.983.5) and new services

o Enhancement of G.983.3 to include 622.080 Mbit/s upstream rate

o Gigabit PON (2.48832 Gbit/s ?)

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Q.3/15 - Support for Recommendations Specifying Systems Based on ISDN

Physical Layers

Currently working on:

o Possible revision of of I.414 (Overview of Access Recommendations) as necessary to incorporate VB5 interface, and other recent new Recommendations in the area of access

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Q.4/15 - Transceivers for customer access and

in-premises phone line networking systems on metallic pairs

Recommendations

o G.991.1 - High bit-rate Digital Subscriber Line (HDSL)

o G.991.2 - Single-pair High-speed DSL (SHDSL)

o G.992.1 - Asymmetrical DSL (ADSL)o G.992.2 - ‘Splitterless’ or ‘lite’ ADSLo G.992.3 - ASDL 2 (2nd generation ADSL)o G.992.4 - Splitterless or ‘lite’ ADSL 2

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o G.993.1 - Very high bit rate DSL (VDSL) – Foundation

o G.994.1 - DSL Handshaking procedureso G.995.1 - Overview of DSL Recommendations

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o G.996.1 - DSL Testing procedureso G.997.1 - DSL Physical Layer management o G.989.1 - Phone-line Networking - Foundationo G.989.2 - Phone-line Networking - Payload

format and Link Layer requirements

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G.991.1 - High bit-rate Digital Subscriber Line transceivers

o Two wire bidirectional transceiver, three systems:

o Two or three pairs, each 748 kbit/so Two pairs, each 1168 kbit/so One pair, 2320 kbit/so Line Code - 2B1Q or CAP (Carrierless

Amplitude and Phase modulation)

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G.991.2 - Single pair High-speed Digital Subscriber Line transceivers

o Duplex (bidirectional) operation on one copper pair

o Payload 192 kbit/s up to 2.312 Mbit/so Optional 2 pairs: Payload 384 kbit/s up to

4.624 Mbit/so Line Code - TC-PAM (Trellis Coded Pulse

Amplitude Modulation)

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G.992.1 - Asymmetric Digital Subscriber Line transceivers

o One twisted pairo Payload upstream up to 640 kbit/so Downstream up to 6.144 Mbit/so Simultaneous Voiceband and N-ISDN

possibleo Line Code - DMT (Discrete MultiTone)

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G.992.2 - Splitterless asymmetric digital subscriber line transceivers

o One twisted pairo Payload downstream up to 1.536 Mbit/so Upstream up to 512 kbit/so Line Code - DMT (Discrete MultiTone)

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G.993.1 - Very high bit-rate Digital Subscriber Line transceivers

o One twisted pairo Asymmetric and symmetric data rates up

to tens of Mbit/so Frequency Division Duplexing to separate

upstream & downstream traffico Three band plans defined occupying

138kHz up to 12 MHz

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G.989.1/G.989.2 – Home Phoneline Networking Transceivers

o In-premises distribution of data over existing phoneline wiring

o Nominal effective throughput equal to 10BASE-T Ethernet

o Compatibility with other phoneline services such as POTS, V.90/V.92, ISDN and G.992.2

o Spectrum notching for compatibility with Amateur Radio services

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Q.4/15 - Transceivers for customer access and in-premises phone line

networking systems on metallic pairs

Current/future work

o Revision of Single-pair High-speed DSL (SHDSL) - G.991.2

o Second Generation ADSLo Second Generation‘Splitterless’ ADSL

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Q.4/15 - Transceivers for customer access and in-premises phone line networking systems on metallic pairs

Current/future work (continued)

o Very high bit rate DSL (VDSL) – G.vdsl.lo Phone-line Networking - Isolation Filter –

G.pnt.ifo Voice over DSLo Bonding of DSL systemso Power Line Transmission (in-premises

only)?

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G.991.2 (SHDSL) transceivers

Multi-rate transmission technology duplex operation over only two-wire twisted metallic

pairs. (G.991.1 is for 1-3 pairs).

Symmetric data rates (scalable): One pair mode: 192 kbit/s to 2312 Kbit/s (single pair

mode), in increments of 8 kbit/s, distance from 1.8 up to 6.5 km.

Two-pair mode: 384 kbps to 4.624 Mbps

Many Manufacturer’s options 4-wire operation Repeaters, etc.

ITU-TITU-TSG15SG15


G.993.1 (VDSL) transceivers

Symmetric and asymmetric data rates Downstream as high as 5 to 20 Mbit/s Upstream 1.6, 2.3, 19 Mbit/s or equal

to downstream in case of symmetric tx. American/Japanese/European

Service Types (Annexes) 300 – 1 500 m. reach

Documents

ITU-TSG15 ITU-T Standardization Seminar – Madrid, 12-13 December 2002 Optical and xDSL Access work in ITU-T Study Group 15 Presented by: Simão Ferraz de