DSL - Digital DSL - Digital Subscriber LineSubscriber Line

An OverviewAn Overview

Presented by Team 1Presented by Team 1

November 17, 2001November 17, 2001

ADSL ADSL ContentsContents

Origins of ADSLOrigins of ADSL DefinitionDefinition ADSL Standards – USADSL Standards – US Typical ADSL InstallationTypical ADSL Installation Technical DescriptionTechnical Description EvaluationEvaluation A View to the FutureA View to the Future

Origins of ADSLOrigins of ADSL

Availability of CablingAvailability of Cabling Need for Faster Need for Faster

CommunicationCommunication Internet EXPLOSION!Internet EXPLOSION! Expense of ISDNExpense of ISDN Emergence of Emergence of

TelecommutingTelecommuting New ApplicationsNew Applications

DefinitionDefinition

Asymmetric DSL (ADSL)Asymmetric DSL (ADSL)““a modem technology that a modem technology that

converts existing twisted converts existing twisted pair telephone lines into pair telephone lines into access paths for access paths for multimedia and high speed multimedia and high speed data communications.”data communications.”

Source:Source: "ADSL Tutorial: Twisted Pair "ADSL Tutorial: Twisted Pair Access to the Access to the Information Highway," Information Highway," http://www.http://www.adsladsl.com/.com/aboutdslaboutdsl//adsladsl_tutorial.html_tutorial.html

ADSL Standards - ADSL Standards - USUS

ANSI T1E1 working group ITU-T Study Group 15 ADSL Forum

– Recommends end-to-end ADSL architectures, including the higher layer protocols needed to make ADSL systems useful products.

Typical ADSL Typical ADSL InstallationInstallation

Technical Technical DescriptionDescription

GeneralGeneral

Frequency:Frequency: Above 25kHzAbove 25kHz– POTS POTS Below 4kHzBelow 4kHz

Modulation:Modulation:– DMTDMT Discrete Multi-toneDiscrete Multi-tone– CAPCAP Carrier-less Amplitude/ Carrier-less Amplitude/

Phase ModulationPhase Modulation– QAMQAM Quadrature Amplitude Quadrature Amplitude

ModulationModulation Medium:Medium: Unshielded Unshielded

Twisted PairTwisted Pair– 24 AWG (~.5m)24 AWG (~.5m)– 26 AWG (~.4m)26 AWG (~.4m)

Technical Technical DescriptionDescription

Transmission RatesTransmission Rates

Class IClass I 6,175 Mb/s6,175 Mb/s– 6,000 ft6,000 ft 26 AWG loops26 AWG loops

Class IIClass II 4.632 Mb/s4.632 Mb/s– 8,000 ft8,000 ft 26 AWG26 AWG

Class IIIClass III 3.088 Mb/s3.088 Mb/s– 12000 ft12000 ft 24 AWG24 AWG– 9000 ft9000 ft 26 AWG26 AWG

Class IVClass IV 1.544 Mb/s1.544 Mb/s– 18000 ft18000 ft 26 AWG26 AWG

Installation Installation ComponentsComponents

.

Public SwitchedVoice Network

Central Office

High SpeedData Switch

IP Data

Telephone

Fax

Home PCw/Ethernet NIC& IP Address

CombinedVoice and IP Data

Copper Wire

Splitter

IP Data

DSLAM

Voice

Laptop computer

AnalogModem

ADSL ModemATU-R

ToInternet

Source: Paradyne, Inc.

ADSL - An ADSL - An EvaluationEvaluation

Targeted MarketplaceTargeted Marketplace Chief CompetitorsChief Competitors Price ConsiderationsPrice Considerations EconomyEconomy Other BarriersOther Barriers

ADSL - A View to ADSL - A View to the Futurethe Future

Interim StrategyInterim Strategy– Copper Copper – Cable Cable – FiberFiber

Telecommunications Telecommunications Shake-OutShake-Out

Emergence of True Emergence of True Wireless SolutionsWireless Solutions