Fixed Networks Migration towards NGN...ITU-BDT Seminar on Network Evolution, Sofia, Bulgaria, 21- 24 Jan 2003— 2 Why a Next Generation Network ? > Convergence between the packet-based

Fixed Networks Migration towards NGN

Souheil MARINEProduct Strategy Manager

All rights reserved © 2003, AlcatelITU-BDT Seminar on Network Evolution,Sofia, Bulgaria, 21- 24 Jan 2003— 2

Why a Next Generation Network ?

> Convergence between the packet-based Internet and telephonynetworks• Driven by technological evolution• Demand for a network capable of introducing new services

> Take the best from each• Service provision of the telephony network model• Openness and flexibility of the Internet model

> Possible Definition of a Next Generation Network• A packet transport based network where the transport, control and

service layers are separated from each other and interact throughopen interfaces

> The target is well defined but how to reach it ?


Migration Rationale

> Migration of current telephony networks (2 billion users worldwide)should preserve the existing investments

> Key investments in any network are in provisioning access for end-users to the network services (80% of the costs)• Any technological changes become costlier when they get closer to

end-users and should be justified by added value brought with them

> Migration must be driven by basic principles• Continuity of services offered to end-users• Inter-working between new and old technologies• Cost control of the migration process

> Migration should above all be driven by economic considerations• Network consolidation and optimization and/or• New revenues driven from new services


Proposed Migration Approach

> Stepwise approach where each step is justified by new servicesor advantages brought from consolidation

> The proposed migration steps are generic• Application of each step depends on the specific operator context• All are not compulsory and do not follow in the same sequence• There is no “one size fits all” migration scenario

> Network views of migration steps are not exhaustive• Emphasis put on significant network elements needed for service

provision, on signaling relations between end-users and thenetwork and between network entities

• Emphasis put on fixed access networks though the approach is verysimilar for mobile networks evolution (see tomorrow’s presentation)


Access to the Internet and ConvergedInternet/Telephony services

POTS,ISDN

Local

VoiceDataSignaling

Internet

PacketNetwork

Dial-upModem

DSLAM

BAS

DSLModem

‘PINT’, ‘SPIRITS’

Parlay, JAIN, SIP

ApplicationServers

WWWServers

SS7

Local

Transit

TDM

STP

INAP

ISUP

Access Node

SCP

ISUP

Transit

NAS

ISDN/PRA

ApGW

Intelligent NetworkServices

Intelligent NetworkServices

Internet AccessDial-up and DSLInternet Access

Dial-up and DSL

Basic Telephony Services

Basic Telephony Services

Converged Voice and data ServicesConverged Voice and data Services


Access to the Internet and ConvergedInternet/Telephony services

> Basic telephony service and its associated supplementary services• TDM based transport• SS7 based signaling

> Intelligent Network Services• Calling Cards, Free phone,Voice virtual private networks,…

> Internet access• In dial-up mode or in broadband mode with DSL technology

> Converged Voice/data services• Benefit from the simultaneous availability of a telephony access and

Internet access in the case of broadband Internet access• Examples of converged services: Click-to-Dial, Internet Call Waiting,

Web Augmented Calling, Unified Messaging,...


Network consolidation: evolution towards multi-serviceaccess nodes and Internet traffic optimization

Internet

PacketNetwork

POTS,ISDN

SS7

ADSL-NT

Transit

Local

SCP

Voice

STP

DSLAM

Local

INAP

V5.2

Multi-serviceAccess Node

TDM

VoiceDataSignaling

ISUP

ISUP

Multi-serviceAccessNodes

V5.2 or proprietary

ATM, IP

NAS

BAS

ISUP (IMT)

Switch Capacity Enhancement

Switch Capacity Enhancement

Legacy and Broadband

Access

Legacy and Broadband

Access

BroadbandAccess

BroadbandAccess

Internet Dial-up traffic connectivity

in SS7

Internet Dial-up traffic connectivity

in SS7


Network consolidation and introduction ofnew multi-service access nodes> Switch consolidation

• Maximize number of line, minimize number of nodes• Upgrade of switch fabric and processors for higher capacity and

speed

> Access Consolidation• Introduce NGN-ready multi-service access nodes

– End-user can be in native packet access mode– DSL but also other alternative next generation local loop technologies

(cable networks, wireless local loop, satellite,…)– Introduce Voice-over-DSL (loop emulation service) and extend voice

service offer without modification of the legacy switches

> Optimize interconnection to the data network for dial-up access• Interconnection at local exchanges level (offload transit level)• Use of ISUP and Inter Machine Trunks (IMT) instead of ISDN/PRA


Voice over Packet for Trunking

PacketNetwork

SS7

Local orTransit

SCP

STP

Local orTransit

TDM

INAP

BICC

VoiceDataVoice/PacketSignaling

Internet

IntegratedGateway

ISUPTransit

ISUP

INAP

H.248

ISUP, BICC, SIP-T

Switch with MGCfunction

Offload of voice traffic to packet

network

Offload of voice traffic to packet

network

Voice Network Consolidation

Voice Network Consolidation

Quality of Service

at Aggregatelevel

Quality of Service

at Aggregatelevel

Transparencyof Packet Voice

use for end-user services

Transparencyof Packet Voice

use for end-user services


Voice over Packet for Trunking

> Gradually offload voice trunking traffic to the packet network

> Network consolidation by removal of an upper transit level oroptimization within a transit level• Voice-over-Packet trunking through integrated gateways in the

LEX/TEX• Alternative solution based on external trunking gateways controlled by

a Switch with Media Gateway Control (MGC) function• Use of SS7 based BICC signaling for co-existence with PSTN/ISDN

services• Reuse of existing IN services for business continuity

> First mastering of voice over packet technology at aggregate level• Simpler Quality of Service issues

> Service transparency of Voice over Packet use for end-users


Voice over packet up to access level

PacketNetwork

SS7

Local

SCP

STP

AN

TDM

CentralisedAccess Gateway

DSLAM

H.248

INAPInternet

Switch with MGCfunction

ISUP

VoiceData

Voice/ PacketSignalling

Transit

ISUP

Access Gateways closer to end usersAccess Gateways

closer to end users

Control of accessgateways from Switch with MGC

function

Control of accessgateways from Switch with MGC

function


Voice over packet for access

> Extend use of packet transport to the access network for voiceservices• Introduction of Access Gateways

– Integrated within next generation multi-service access nodes or– Standalone centralized access gateways

• Access gateways are controlled by a switch with MGC function– Same services portfolio as on the PSTN/ISDN– Tighter integration of voice and packet services

> Improved network consolidation• control of the voice traffic from fewer Switches with MGC function• Voice traffic gradually moved from the control of old generation

switching equipment to the control of upgraded MGC switches


Multimedia Services

Internet

WWWServers

PacketNetwork

SS7

Local

SCP

STP

AN

Transit

TDM

Softswitch

DSLAM

BAS

ApplicationServers

Portal

SIPParlay JAIN

SIP

SIP, H.323

HTTP

VoiceData

Voice/PacketSignalling

INAP

ISUPISUP

ISUP

H.248

End-users shift tonew terminals

End-users shift tonew terminals

End-user to softswitch dialogue withnew protocols

End-user to softswitch dialogue withnew protocols

Next Generation Access node handle

resources for MM calls

Next Generation Access node handle

resources for MM calls

Openness to 3rdparty services

Openness to 3rdparty services Multimedia

Softswitch MultimediaSoftswitch


Multimedia Services

> End-users connected through next generation multi-serviceaccess nodes will adopt IP terminals for multimedia services• Better benefit of the high bandwidth, always-on and interactivity

associated with such next generation access networks

> New IP terminals will be controlled by Multimedia Softswitchesthrough a new type of NGN signaling• SIP or H.323• Access network will focus on resource provision under the softswitch

control depending on the service used

> A multimedia softswitch offers network services but also thirdparty services through portals and open interface• Network operator becomes the intermediary broker between

application providers and their clients


Conclusions

> Services are key drivers for the evolution of telecom networks• NGN is more than just broadband access to the Internet• Broadband access is a necessary but not sufficient condition ! It is

above all an enabler of new services with new revenues• NGN must build on the strengths of the telephony service model

albeit being based on technologies coming from the Internet

> NGN emergence will happen but will take time• PSTN networks will continue to provide the voice telephony service

for a while• State-of-the-art PSTN solutions of today will evolve to be part of the

future NGN picture• Some technical issues (QoS, naming, signaling) must be matured

for new NGN services to become a mass market phenomenon• NGN must above all bring new services to be meaningful

www.alcatel.com

Thank You !Questions ?

Documents

Fixed Networks Migration towards NGN...ITU-BDT Seminar on Network Evolution, Sofia, Bulgaria, 21- 24 Jan 2003— 2 Why a Next Generation Network ? > Convergence between the packet-based