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 Thursday, 28 February 2008

ITU experts have reported a good spirit of cooperation following a meeting with counterparts from the Internet Engineering Task Force (IETF) on the topic of T-MPLS, during February’s Study Group 15 meeting in Geneva.

The Ad-Hoc Group on T-MPLS met to iron out perceived inconsistencies between MPLS developed by IETF and T-MPLS developed in ITU-T. The meeting appointed Malcolm Betts as ITU representative and Dave Ward from IETF.

A joint working team (JWT) has been created with experts from ITU-T and IETF.

Previously the IETF requested that the ITU-T either: (1) Work in cooperation to extend the IETF's MPLS technologies through the IETF Standards Process or: (2) Decide to use its own Ethertypes and maintain separation of codepoints in the future, change the name of the technology so it is not easily confused with IETF MPLS and work independently.

The JWT will allow the IETF and ITU-T to work in close collaboration on T-MPLS to understand the implications of these options and facilitate the subsequent development of solutions that ensure that the required degree of MPLS/T-MPLS compatibility, consistency, and coherence, recognizing that the sole design authority for MPLS resides in the IETF, and the domain of expertise for Transport Network Infrastructure resides in ITU-T SG15.

It is expected that the group will use remote collaboration tools and make a decision on which way to progress by April 2008. See also previous newslog entry here.

MPLS is widely embraced in backbone networks as a way to speed up routers. Lately some have advocated its use further downstream in access networks, there have even been suggestions to extend this as far as customer premises. ITU’s work seeks to support this, but additionally to allow the seamless interworking between Ethernet and MPLS. This has been progressed in SG 15 through the completion of a new set of Recommendations for Transport MPLS (T-MPLS), a technology which uses a subset of the components defined in the MPLS Layer Network Architecture of Recommendation G.8110 to support packet transport applications that adhere to ITU-T layer network architecture principles. A T-MPLS layer network can operate independently of its clients and its associated control networks (i.e., multi-carrier or single carrier networks (MCN, SCN) and can carry a variety of client traffic types. This independence affords network operators the freedom necessary to design robust packet transport networks for their own use and to transport customer traffic. T-MPLS is designed to behave consistently with existing transport technologies, thus offering the operational characteristics, performance and reliability that network operators require from carrier-class technologies. The new Recommendations for this technology cover the T-MPLS layer network architecture (G.8110.1/Y.1370.1), interfaces for the T-MPLS Hierarchy (G.8112/Y.1371), and T-MPLS Equipment (G.8121/Y.1381).