I have reviewed this document as part of the security directorate's ongoing effort to review all IETF documents being processed by the IESG. Document editors and WG chairs should treat these comments just like any other last call comments. SECURITY The Security Considerations section is brief but covers most of the considerations that specifically occurred to me in reading this draft. In Section 3.5.2 there are various fields that MUST be unique. Are there security consequences if they are not? MINOR A reference to RFC 6291 should probably be included. Section 2.1: CC is not listed. P/F is not listed. Section 3.7.4.1: I believe all the figure numbers in this section are wrong. EDITORIAL Abstract: "integrity of the continuity" seems redundant. Just "continuity" is better. Abstract: "any loss of continuity defect". So you lost a "continuity defect", did you? Slipper little guys, aren't they? Maybe you mean "any loss-of-continuity defect". Introduction: I don't get the reason for the double references like "[12][12]" and "[13][13]". Introduction: Missing commas: "the same continuity check (CC) proactive continuity verification (CV) and remote defect indication (RDI) capabilities" should be "the same continuity check (CC), proactive continuity verification (CV). and remote defect indication (RDI) capabilities". Section 2.1: This is just a personal preference of mine but I think it is best to explain a little more than you think you need to. So I would include entries for MPLS, OAM, and PDU. Figure 4, Figure 6: There should be a blank line after the Figure label. Figure 5, Figure 7, Figure 8: Figures should not be broken over page boundaries. Section 4, Section 6: No blank line before Section header. Section 4: Ends with a list of length 1. List constructs should not be used for lists of length one. Overall: As in many such documents, I believe that acronyms are overused and the document would be improved by more frequently spelling things out. For example, p2p occurs only twice in the document, the first time when it is also spelled out and only one other use. I believe such rarely used acronyms should generally be spelled out for all of their tiny number of uses. Thanks, Donald =============================  Donald E. Eastlake 3rd   +1-508-333-2270 (cell)  155 Beaver Street  Milford, MA 01757 USA  d3e3e3 at gmail.com