Asymmetric Digital Subscriber Line

Tutorial Slide Show

Tutorial Outline What Is ADSL ? What Can ADSL Do ? How Does It Work ? Architectural Options Status of the Technology The Future

ADSL Equipment

ResidentialCustomer

Remote ADSLUnit

Customer Premises

Equipment

Central Office Building

ADSL Rackof Line Cards

Standard Telephone Lines

Data & Telephony on One Line

Data as ATM Cells &/or IP Packets

TV FastInternetAnything that can be digitised

All in Addition to Existing Analogue Telephony

“Evolution of Digital Access”

VoicebandModem

ISDN

ADSL

FTTH

FTTx + VDSL

Today

EnhancedCopper

Hybrid Fibre/Copper

Pure Fibre

“Tomorrow’s Network” : ADSL

ADSL

1.5 to 8Mbit/s9.6 to 640kbit/s

Broadband NetworkInternet

Video Servers

LiveBroadcast

TelephoneNetwork

Typical Network Construction

Central Office

Street Cabinet

OverheadFeed

UndergroundFeed

Feeder Network Distribution Network

Next Topic

What Is ADSL ? What Can ADSL Do ? How Does It Work ? Architectural Options Status of the Technology The Future

ADSL Applications

Internet Access, etc. LAN Access (Teleworking) Distance Learning Broadcast TV Home Shopping Video On Demand

Next Topic What Is ADSL ? What Can ADSL Do ? How Does It Work ? Architectural Options Status of the Technology The Future

How Does ADSL Work? Functional Elements Use of Bandwidth Channel Separation & POTS Splitter Transmission Methods

Discrete Multi-tone Modulation (DMT) Quadrate Amplitude Modulation (QAM) Carrierless Amplitude/phase

Modulation (CAP)

ADSLModem

POTSFilter

Mbit/s

kbit/sADSL

Modem

POTSFilter

POTSLinecard

Mbit/s

kbit/s Line

Exchange End Customer End

ADSL Modem Structure

ADSL Modem Functions

Rates/multiplexingForward Error Control (FEC)

Framing/mappingProtocol processing

OAM processing

Transmission Convergence

Alternatives

Bit Synchronous (STM)Packet ModeATM Mode

Line Code (modulation)Initialisation

POTS splitter/interfaceScrambler/descrambler

Base EOC functions

Physical Media Dependent

Alternatives

DMTQAMCAP

Baseband

LineInterface

DigitalInterface

ADSL

HDSL

ISDN

VDSL

Growth in Bandwidth Utilization

Bandwidth (MHz)

Time

10+ MHz~1 MHz~0.5 MHz~0.1 MHz

~1986

~1990

~1994

~1997/8?

Next Topic What Is ADSL ? What Can ADSL Do ? How Does It Work ? Architectural Options Status of the Technology The Future

Data-Centric Architecture

CPEor PC

ISPADSL

LinecardRouter

EthernetHub/Switch

10 base TEthernet

10 base TEthernet

10 base T or

100 base T

45 or 155Mbit/s

ATM or FR

ADSLRemote

Telecom-Centric Architecture

CPEe.g. PC or STB

ADSLAccess

Mux

ADSLLinecard

ISPATM

155 Mbit/sfibre

ATMe.g. 25 Mbit/s

ADSLRemote

Next Topic

What Is ADSL ? What Can ADSL Do ? How Does It Work ? Architectural Options Status of the Technology The Future

Status of ADSL Technology

Equipment Standards Trials

ADSL Equipment Trends More Choice of Transceiver Chips and

Equipment Increased Transceiver Integration More Transceivers Per Line Card and

Equipment Rack More Customers Per Exchange Transceiver Faster Transmission Speeds Increased Embedded Internetworking

Functionality

Standards and Recommendations

ANSI ETSI ADSL FORUM DAVIC ATM FORUM ITU

ADSL Activities Throughout the World

ADSL Activities in the USAADSL Activities in Asia & Australasia

ADSL Activities in Europe

Next Topic What is ADSL ? What can ADSL do ? How does it work ? Architectural Options Status of the technology The Future

Broadband NetworkBroadband Switch Network (eg. ATM)

Service Providers

Servers&

Billing

Access Network

OperationalSupport System

New OpticalCable

ADSL

Local Exchange

VDSL

POTS

High-Capacity Backbone Links

“Evolution of Digital Access”

VoicebandModem

ISDN

ADSL

FTTH

FTTx + VDSL

Today

EnhancedCopper

Hybrid Fibre/Copper

Pure Fibre

Asymmetric Digital Subscriber Line

Introduction Slide Show

Thank You for watching!