MPLS-TP linear protection for ITU-T and IETF

Abstract

The MPLS Transport Profile (MPLS-TP) is a framework for the construction and operation of reliable packet-switched transport networks based on the architectures for MPLS and Pseudowires. Its development has been shared between the IETF, where the MPLS expertise resides, and the ITU-T, with its historic understanding of transport networks. MPLS-TP adds two significant features to the MPLS toolkit: Operations, Administration, and Maintenance (OAM), and linear protection switching. Unlike OAM, which resulted in two application specific and incompatible standards being approved at the World Telecommunication Standardization Assembly (WTSA) in November 2012, the MPLS-TP linear protection specification has resulted in a single unified solution that has been published in IETF RFCs and in ITU-T Recommendation G.8131. This article outlines the novel concepts and operation principles of the unified MPLS-TP linear protection switching mechanism and discusses how it differs from pre-existing solutions. In addition, the issues of compatibility with pre-existing solutions and the applicability to other network topologies are discussed.