VoDSL

Voice over DSL

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Overview

• History• Introduction DSL• Introduction VoDSL• Requirements• DSL Growth• Architecture• CVoDSL• VoMPLS

DSL

Developed in 1989, designed primarily for video

ADSL was the first type („high downstream“ for Video)

When DSL was first developed in 1989 it was designed primarily for video. ADSL wasthe connection of choice because it provided the high downstream rates that wereneeded for streaming video. Video on Demand (VOD) was viewed as the nextgeneration service supporting the next generation network from telephone companiesaround the world. Video on Demand was expected to be the telephone company's wayof competing with cable television providers, and ADSL was the technology to make itpossible. However, with few exceptions, VOD has not proven to be as popular as wasonce predicted.

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Introduction DSL

• Digital Subscriber Line• Provides high speed Internet access through

existing telephone lines (copper lines).• Internet access and phone calls can be done

simultaneously• no dial-up procedure before internet access• Many different DSL Occurrences(xDSL):

ADSL, H(igh Data Rate)DSL, V(ery High data Rate)DSL,S(ymmetric)DSL…

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Introduction VoDSL

• Means Voice over Digital Subscriber Line (DSL)

• multiple telephone lines and high speed data servicesover a single access line.

• dynamic sharing of the DSL bandwidth between voicecalls and data services.

• Provides the ability to purchase voice and data servicesfrom a single provider

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Requirements(VoDSL)

• Reliability• Quality

• Digitalisation , Compression should not benoticeable(hearable)

• Feature Support• Caller ID, Call Waiting, Voice Messages, DTMF tones etc.

• Support of existing Customer Equipment• Analog Phones (tone- and pulsdialing)• Fax and Modems etc.

• Scalability

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DSL - Growth

• Last year increase – December 2002 toDecember 2003• 27.94 Millionen

• Global Subscribers Reach 63.8 million -March 2, 2004

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DSL - Growth

©

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DSL - Growth

5.21,820,230UK10

10.92,170,243Canada9

8.32,280,000Italy8

21.42,800,000Taiwan7

9.63,262,700France6

8.44,500,000Germany5

27.76,435,955South Korea4

4.89,119,000USA3

14.410,272,052Japan2

5.110,950,000China1

DSL per100 phone lines

31 December 2003

DSL Subscribers31 December 2003CountryGlobal Ranking

©

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DSL - Growth

• competitive local exchange carrier• Telecommunications Act: The Act allows companies

with CLEC status to use ILEC infrastructure

• incumbent local exchange carrier• telephone company that was providing local service

when the Telecommunications Act was enacted

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Architecture

• The architecture defines three main components:

• Integrated Access Device (IAD)

• DSL Access Multiplexer (DSLAM)

• Voice Gateway

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Voice Switch Center

PSTN

Customer Voice and Datatraffic is combined on asingle Digital SubscriberLine via an IntegratedAccess Device (IAD).

PBX

Central OfficeCustomer Premise

VoiceGateway

Voice Switch

Traffic from manycustomers is concentrated

in the Central Office orother traffic aggregation

point.

Voice traffic is sent tothe PSTN (public

switched telephonenetwork) through a

Voice Gateway.

IADDSLAM

DSL

Architecture

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• DSL Forum VoDSL Models :

• Broadband Loop Emulation Service (BLES)

• Voice over Broadband Networks (VoMBN)

Architecture

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DSL Forum BLES Model

Small Business Client

LAN

Ethernet

ATM

DSL

CPE

Internet

Integrated voice and data Access Network

Voice Provider

POTS... KeySystem

PSTNVoiceSwitch

( Class 5)Gateway

ATMSwitch

DSLAM ATMSwitch

CPE: Customer premiseequipment

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Broadband Loop Emulation Service

• Attaches to the Class 5 switch using well-knownand proven standard interfaces• VoDSL Systems transparently derive voice services

from Class 5• Dial tone, Voice Mail,• Caller ID, Call wait, Call forwarding,…

• Allocates bandwidth dynamically• Voice calls are given priority• Data calls using remaining bandwidth

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Voice overBroadband Networks

• Using softswitch technology to deliver value-added services over DSL at the network edge

• Class 5 switching architecture is expensive, andlimits the ability of service providers todifferentiate.

• MBN will support end-to-end data networkconnectivity for voice calls

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Voice overBroadband Networks

• What are Broadband Networks?• Networks which carry multiservice traffic• (Other terms are Integrated Networks or Multiservice

Networks)

• What is multiservice traffic?• Anything which can be encoded in bits

• Audio e.g. Voice• Video e.g. HDTV pictures• Data e.g. File transfer

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Voice overBroadband Networks

• The advantages of this architecture are:

• provide IP-based enhanced services

• all call protocols are provided outside a Class 5 switch

• equipment at subscriber is very much like that for BLES

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VoDSL Architecture - VoMBN

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VeDSL

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POTS 512 kbpsupstream

1536 kbpsdownstream

Hz

...

PCM voice channel (64Kbps)

Use one of ADSL Channels as Voice Channel

Copyright© 2000 Samsung Electronics Co.,LTD

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CVoDSL

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VeDSL vs. VoDSL

AAL2

Echo Canceller

ATM

Compression

Codec

SLIC ADSL Phy

VoDSL (Broadband Loop Emulation Service)

VeDSL(Voice Enabled DSL)

Codec

SLIC ADSL Phy

To DSLAM

To DSLAM

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VoMPLS

• The term “Voice over MPLS” (VoMPLS) defines amethod to transport encoded voice directly overMPLS

• Voice samples are encapsulated in the MPLSprotocol

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VoMPLS

• VoMPLS Benefits• Efficient transport mechanism for packetised voice by

reducing header overhead.• Support of efficient multiplexing of multiple voice calls

over a single LSP• Usage of label switched paths as a bearer capability to

provide predictable and constrained QoS

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VoMPLS Reference Architecture

MPLS Forum 1.0

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THANK YOU!!