The IESG has approved the following document: - 'MPLS Transport Profile (MPLS-TP) Linear Protection to Match the Operational Expectations of SDH, OTN and Ethernet Transport Network Operators' (draft-ietf-mpls-tp-psc-itu-04.txt) as Proposed Standard This document is the product of the Multiprotocol Label Switching Working Group. The IESG contact persons are Adrian Farrel and Alia Atlas. A URL of this Internet Draft is: http://datatracker.ietf.org/doc/draft-ietf-mpls-tp-psc-itu/ Technical Summary This document describes alternate mechanisms to perform some of the MPLS-TP linear protection sub-functions defined in RFC 6378. It also defines some additional mechanisms. The purpose of these mechanisms is to closely model the behavior of linear protection seen in other transport networks. This document also introduces capabilities and modes for linear protection. A capability is an individual behavior, and a mode is a particular combination of capabilities. Two modes are defined PSC mode and APS mode. The document describes the behavior of the PSC protocol including when all the capabilities of the APS mode are enabled. The document describes priority logic and the protocol state machine. The document updates RFC 6378 in that the capability advertisement method defined here is an addition to that document. Working Group Summary This document has a rather long history. It is intended to match the operational practices and methods that have been used by transport network operators prior to the introduction of MPLS. When RFC 6378 was progressed it was decided that backwards compatibility with deployed MPLS networks was the priority. Later the discussion on meeting the requirements from transport network operators re-emerged and it was decided that the solution should be based on RFC 6378. To that end RFC 6378 had to be slightly extended and modified. There were 5 capabilities missing in RFC 6378, these were the extensions. There were also cases where relative priority between different actions need to be changed, these were the modifications. The first approach were to write a single document for each capability (at the time it was thought that the capabilities might be activated independently), The discussion in the working group however converged on putting all the capabilities in one document. The first MPLS Review Team review and the discussion in the working clearly indicated a wish to make the merged document a working group document, so the chairs initiated a second MPLS Review Team review and took the decision to make it a working group document without running the normal WG adoption poll, instead evaluating the discussion on the mailing and their own review. . The document has, nevertheless been well discussed within the working group. After that the document became a working group document there has been a good and open discussion on the mailing. It is the Shepherds opinion that the document is ready for publication. Document Quality An implementation poll has been sent to the working group mailing list and the write-up will be updated if and when the information is available. There are strong indications of vendor interest. There is a long list of important reviewers, especially the MPLS Review Team reviewers that contributed the arguments that resulted in the current document structure and that also did a careful technical review. Personnel Loa Andersson is the document shepherd Adrian Farrel is the responsible AD
