MPLS-TP Linear Protection ietf-mpls-tp-linear-protection

1. Nurit Sprecher (nurit.sprecher@nsn.com), Annamaria Fulignoli (annamaria.fulignoli@ericsson.com), Stewart Bryant (stbryant@cisco.com), Eric Osborne (eosborne@cisco.com), Yaacov Weingarten (yaacov.weingarten@nsn.com) MPLS-TP Linear Protectionietf-mpls-tp-linear-protection

2. Since we saw you last • Received comments on the mailing list • Partly editorial • Highlighted some small inconsistencies between different statements (use of Fpath and Path fields) • Requested clarification of the Principles of Operation • Pointed to possible technical problems with state transitions • Requested more alignment with ITU APS protocol format • To address the comments the editors and authors have held off-line discussions • Addressed editorial comments directly • Defined new states to address technical issues • Clarified the issues of input priorities and state transitions

3. Operative conclusions • Principle of operation – • Separate priority of local inputs from other parameters • Request field reports local status at end-point • Path field identifies traffic carried on protection path • Adding support for additional states • Normal, Unavailable, Protecting administrative, Protecting failure, WTR, DNR • Clearly define how end-point reacts to different inputs • State dependent – of local or remote origin • Differentiate reaction to local and remote inputs • Specify what message is generated in each case

4. Additional features -considered • Support for 1:n protection • Could be single-phase by allowing the protection path to simultaneously protect multiple paths (statmux 1:n) – future applicability document • Multiple-phase, similar to TDM 1:n protection – where protection path dedicated to protecting a single working path (mutex 1:n) • Would need future draft and use extension

5. Next steps • New revision just uploaded – based on the reconsiderations • Request comments and contributions to make the draft more complete