All information on this slide is indicative - For discussion purposes only

21CN Implementation & Strategy

21CN CORE TRIAL

Keith Davies

All information on this slide is indicative - For discussion purposes only

DistributorNode

AggregatorNode

MetroNode

CoreNode

Physical metronode location

Physical corenode location

Cabinets / PCPs MSAN – initially DSLAM withPSTN/Combo cards or DSL cards

IAD

Separation to IP/MPLS coreGateways – to NGSGateways – to PNOsMedia servers

Call servers

MPLS coreInter-metro nodetrafficCall servers – locatedin data centres with signalling long-lined

21CN NETWORK STRUCTURE VISIONTHE KEY NETWORK NODES & FUNCTIONS

Analogue PSTN

Derived voice

All information on this slide is indicative - For discussion purposes only

Metro node

VOICE - ARCHITECTURE OVERLAY

AggregatorNode

TDM & IPlogical

interconnects

AnaloguePSTN replacement

Consumervoice

Businessvoice

MSAN

POTS

DSL

ISDN

Businessdata

Data centre location

Call servers

Intelligence

TA Mediaserver

Gateway

PErouter

NTE

DSLModem

Terminal adaptor

ADSLmodem

For PSTN features multimedia & mobility services (Including “Broadband Voice” business services)

For tones, announcements,conference, messaging…

Gateway to legacynetworks and PNOs

Provider EdgeRouter

MPLScore

ISDN2/30

All information on this slide is indicative - For discussion purposes only

Metro node

TRIAL ARCHITECTURE OVERLAY

AggregatorNode

TDM logical interconnects

AnaloguePSTN replacement

MSAN

POTS& DSL CombiCard

Metro Node location

Call servers

Mediaserver

Gateway

PErouter

DSL

Modem

ADSLmodem

POTS features

For tones, announcements,conference, messaging…

Gateway to legacynetwork

Provider EdgeRouter

MPLScoreMSiP

BRAS LegacyIP network

All information on this slide is indicative - For discussion purposes only

TRIAL STAGES

Stage 1: PSTN Trunking

Stage 1a: Class 4 Route Bypass

Stage 1b: Class 4 Switch Bypass Stage 2. PSTN local switching + Broad Band

Stage 2a: Class 5 MGCP PSTN ~1000 lines

Stage 2b: Class 5 H.248 ~ same 1000 lines

Stage 2c: Class 5 Multi-vendor MSAN 3000 lines

Stage 4: Class 5 FTTP Link ~1000 lines

All information on this slide is indicative - For discussion purposes only

21C TRIAL CORE NETWORK

Core Router

Metro Edge Router

Metro Node A Metro Node B

100M

STM-64 over DWDM

GEChan STM-1

ATM STM-4

10GE

Undefined

ATM

Media Gateway

Media Server

Media Gateway

Media Server

Core Node C

Grey not installed

Core Node D

Grey not installed

LAN Switch

iNode Node F

Call Server3xSCAx2x100Base

T

iNode Node G

Call Server3xSCAx2x100Base

T

Signalling gateways6x2x100BaseT

Signalling gateways6x2x100BaseT

Cambridge PoP Woolwich PoP

Metro Node E

iNode Node H

Call Server3xSCAx2x100Base

T

Faraday PoP

To MSANs To MSANs

PSTNPSTN

London Central EC PoP

All information on this slide is indicative - For discussion purposes only

TRIAL SERVICES Stage 1

All PSTN & ISDN call types Exceptionally 999/112 traffic is not routed through trial

PSTN

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TRIAL SERVICES Stage 2

Consumer Direct Exchange Line (Analogue POTS) The capability to make 999/112 calls will not be a

guaranteed facility The following call types will NOT be available

a. Calls to the operator (100)

b. Non-geographic special rate (08) except those numbers required for the trial e.g. Service Centre number

c. Premium rate calls (09)

d. International calls (00)

Limited range of PSTN Calling Features

Note. All triallists are BT employees

PSTN

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TRIAL SERVICES Stage 2

Trialists within reach of the service, will, at an appropriate time in the trial be offered BT Broadband 512k service (with modem), which includes 512k broadband access and a Voyager 205 router.

Broad Band

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21CN TRIAL LOCATIONS

Stage 2a &2b

Stage 2c

Stage 1a TrunkRoute Bypass

L/WOOD GREEN EMPIRE WAT

London Central EC Trial Node

WoolwichTrial Node

Cambridge Trial Node&

WAT Bypass (Stage 1b) CRAYFORDWHITTONWOOLWICHCATFORDGROVE PARKBROMLEYELTHAMCHERRY HINTONFELIXSTOWE

Stage 2a & 2b Service Locations

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TRIAL TIMELINE

Stage 1a)….in service

Stage 1b) traffic loading imminent, complete by year end

Stage 2a) customer on load during January 2005

Stage 2b) April / May 2005

Stage 2c) June 2005

Stage 4. Summer 2005

Trial closes December 2005

Present Milestones

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