Internet Architecture Board


January 2006

ITU NGN Liaison Report

Scott Brim
27 January 2006

The ITU-T Next Generation Network Global Standards Initiative (NGN-GSI) meeting just finished. This was a collective two-week meeting of Study Groups 11, 12, 13, 16 and 19. The ITU-T is having trouble partitioning the work, since every topic touches so many technologies, so they are having lots of joint meetings. They are also having problems with feature creep. I couldn’t be everywhere but these are the IETF-relevant issues I picked up:

  • IPv6. The IETF sent a liaison to SG13 Question 9 (9/13) giving them guidance on current work and expected IETF directions for IPv6. They were very appreciative, and have responded with a liaison with more specific information. They mention three specific documents they are working on, but they don’t want to send their documents at this time because they feel like they are too drafty. The titles are:
    • Signaling Requirements for QoS Support at the NGN using IPv6
    • Service Requirements and Functional Capabilities of IPv6-based NGN
    • Framework of IPv6 Multi-homing for NGN

    Two IETF participants volunteered to come to the meeting to provide expert advice, but ITU-T schedules were dynamic and they could not match the changes.

  • There were 10 contributions to SG11 and SG13 concerning “flow-aware QoS control” (see draft-roberts-inband-qos-ipv6-00.txt). The IETF has previously expressed the opinion that it is inappropriate for ITU-T to work on IETF protocols, and the ITU-T has responded positively. At the previous meeting of SG13 the proponents of this approach had been told to restrict themselves to scenarios, architecture and requirements. Rapporteurs reminded them at this meeting, and they agreed to produce a pure requirements document next time.
  • Mobility: NGN-GSI participants essentially understand the various mobility possibilities, at various layers, and they want to apply them. There is a problem of which mobility technologies to use, in which combination, to support mobility at which layer. Do SIP and HIP go well together? The ITU-T may be exploring this issue ahead of the IETF.
  • Fixed/Mobile convergence and RFIDs are also a big topic, covering all participating Study Groups.
  • MPLS: “Voice Trunking over IP” (Y.vtoip) has been consented and will be Y.1452 unless someone objects during the approval process. “TDM-IP network interworking – user plane interworking” (Y.tdmip) will (probably) be Y.1453, assuming SG15 agrees. Q7 are producing a general framework for interworking, which might be useful to PWE3 and L2VPN. 
  • JCA: I attended the NGN Joint Coordination Activity on behalf of the IETF. Issues were administrative, but if we need it we have been given a place at the table and can speak on what the NGN-GSI is doing.