Transcript NGN an architecture for 21st century networks?

NGN an architecture for
21st century networks?
ITU-T NGN Workshop (Geneva, 9-10 July 2003)
Keynote session
Patrice Collet (France Telecom, Director, Network Strategy and
Architecture)
FT/Networks and Carriers Division
ITU-T WORKSHOP on NGN (Geneva 9-10 July 2003)
- D1 -
FT global network evolution
context
A very competitive environment
Keeping network costs as low as possible
Faster return on investment is needed
A strong pressure to tariff decrease
PSTN traffic slowly growing
Shared now between several competitors
A steady data traffic demand growth resulting from Internet traffic
demand
Started with dial up access
Increased with broadband access offers
FT/Networks and Carriers Division
ITU-T WORKSHOP on NGN (Geneva 9-10 July 2003)
- D2 -
Major network evolution
trends (1)
A large ADSL deployment :
End 2002 :
 2000 mdf (out of 12 000) equipped with DSL serving 21 millions lines
 1.4 million users connected
A rapid growth: more than 2 millions users end June 2003
Packet backbones deployment
Expansion of ATM network to collect traffic from DSLAMs
 More than 400 ATM cross connects (starting from 80 in 1998)
An IP backbone deployed serving around 60 PoP in 30 towns
With ADSL a new type of mass market access network is being built
To meet an actual and ready to pay demand: the second time in telecom
history after telephone service
FT/Networks and Carriers Division
ITU-T WORKSHOP on NGN (Geneva 9-10 July 2003)
- D3 -
Major network evolution trends (2)
Stable telephone network
Reduced number of core switches from ≈ 900 to less than 600 end 2002
Decrease of the number of transit exchanges
 To face evolution of interconnection traffic scheme
 And reduce network costs (energy, m², taxes…)
A limited number of new facilities to be implemented (in general IN based)
 Reduction of software releases to be deployed
A good quality of service
No short term obsolescence of switching equipments
 But a part of local exchanges are now roughly 20 years old
–Renewal imagined starting in the second part of the decade
Which technology for the future telephone service?
 TDM network renewal strategy
FT/Networks and Carriers Division
ITU-T WORKSHOP on NGN (Geneva 9-10 July 2003)
- D4 -
Access network perspective
Through its increasing bandwidth, xDSL gives the potential of new services
 New multimedia services integrating voice, data & video could be provided,
 These services are now appearing on the Internet (videophony & videoconference,
streaming of video clips, Web TV, …), but with uncontrolled QoS
xDSL opens the door to residential and SME voice services migration to
packet networks
xDSL deployment shapes the future access network architecture
 ADSL, ADSL2+, SDSL, VDSL interfaces provided by the same DSLAM
 End user fiber connection to DSLAM with ATM traffic concentration
 Integration of video functions
 Digital TV program broadcasting and channel zapping
In some DSLAM implementations POTS connection are or will be provided
 DSLAMs as the future “universal” customer connecting unit?
FT/Networks and Carriers Division
ITU-T WORKSHOP on NGN (Geneva 9-10 July 2003)
- D5 -
NGN as the 21st century
network architecture?
What provides NGN concept ?
A unified packet transport layer for all types of services
A session based control architecture
 For person to person voice or video services over a packet infrastructure
FT expectations from NGN
Be the support of new multimedia services combining voice data and video
 To generate new revenue streams
In addition be the future infrastructure of telephony services
 Shared with multimedia services
 To face the need for renewing PSTN infrastructure (when obsolete)
 While securing voice revenue stream
Be able to combine Internet services and more traditional communication
services
Interest for NGN focussed on access systems
FT/Networks and Carriers Division
ITU-T WORKSHOP on NGN (Geneva 9-10 July 2003)
- D6 -
Some requirements for NGN
implementation
Need for interoperability between equipment providers
Commonly agreed functional and organic architectures needed
A set of standardized interfaces and protocols to be agreed upon
Ability to serve several kinds of access network
Fixed copper, fiber, wireless..
Mobile
An open services architecture
Standard interfaces open to third party service providers
Allowing for Interaction between Internet access services and other multimedia
services
 Probably more a question of role of actors than a technical issue
An architecture based on UMTS (Release 5/6) architecture principles
Including some mobility features at the fixed access: user nomadism
Providing minimum service continuity between fixed and mobile access through
VHE
FT/Networks and Carriers Division
ITU-T WORKSHOP on NGN (Geneva 9-10 July 2003)
- D7 -
Some requirements for NGN
implementation (2)
Need for QoS differentiation
Services like voice, video, need QoS control mechanisms
Especially at the access level
 Limited bitrate access shared between several services
–upstream ADSL channel for example
 Need for bandwidth allocation mechanisms
A set of management functions shared between different services
Self-provisioning, usage metering for billing, QoS monitoring, statistics..
A common technology for transport layer
 IP and MPLS seem the good candidate for such a layer
 Large world industrial support and good evolution speed
 ATM for bandwidth sharing on copper to provide QoS to voice and video services
 Significant efforts of standardisation/ selection of relevant standards work still to be
done
FT/Networks and Carriers Division
ITU-T WORKSHOP on NGN (Geneva 9-10 July 2003)
- D8 -
Architecture : standardization
needs
Service Y
Service X
OSA/WebServices
?
Open interfaces
Management
H323/SIP ?
Separated control
MGCP/H248 ?
FMC ?
ENUM
?
QoS mechanism
?
NB Wireless
Usage
measurement
?
BB Wireless
Unified transport :
BB Wireline
IP/ATM/MPLS ?
Bandwidth sharing
?
FT/Networks and Carriers Division
ITU-T WORKSHOP on NGN (Geneva 9-10 July 2003)
- D9 -
Conclusion
There is an opportunity window for NGN architecture implementation
Obsolescence of TDM systems started to be deployed in the early 80s
Two key questions:
True multimedia capability of this architecture
QoS benefits provided by NGN compared with ISP-like architecture
Some challenges:
Keep an integrated architecture open enough
 To make it capable to quickly and easily evolve
Achieve the necessary industry consensus
 To meet the interoperability requirements
FT/Networks and Carriers Division
ITU-T WORKSHOP on NGN (Geneva 9-10 July 2003)
- D10 -