Study Group 15 saw continued progress in its work on standards to support the end-to-end rollout of Ethernet and Multiprotocol Label Switching (MPLS). This work continues the evolution of the use of Ethernet as an enterprise technology into a carrier service, and supports MPLS from a wider network perspective.

Study group experts say that ITU is the only standards body looking to support the choice of either Ethernet or MPLS as an end-to-end network technology. In effect ITU is addressing both technologies as part of one packet transport network, focusing in addition on their seamless interoperability.

Work in the Ethernet field progressed at the February meeting aims to allow per user, service provider, and network operator service level monitoring and assurance; fault isolation to target maintenance and repair and to enable automatic protection switching, network management and the possibility of reuse of SDH management systems.

This work is based on, and enabled by the work recently completed on Ethernet operations, administration and maintenance (OAM) in Study Group 13 with their consent of new Recommendation Y.1731 (see story). The follow-on work in SG 15 includes amendments to the layer network architecture (G.8010/Y.1306) and the Ethernet equipment Recommendations (G.8021/Y.1341), and a new Recommendation on Ethernet protection switching (G.8031/Y.1342), which according to Study Group experts will give operators the opportunity to offer close to 100 per cent availability of Ethernet services for the first time. This is achieved using a system that uses a predefined alternative route if the most direct is broken.

In the field of MPLS a raft of new work aims to allow operators to adopt this technology end-to-end. 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).