Reviewer: Zhen Cao Review result: Ready with Issues I am an assigned INT directorate reviewer for this draft. These comments were written primarily for the benefit of the Internet Area Directors. Document editors and shepherds should treat these comments just like they would treat comments from any other IETF contributors and resolve them along with any other Last Call comments that have been received. For more details of the INT directorate, see <http://www.ietf.org/iesg/directorate.html>. This version is quite ready to go, with a small issue that I would like to discussion: In Section. 15 (Reliability of Client Initiated Message Exchanges), I strongly recommend that implementation MUST NOT set both MRC or MRD to ZERO, which attaches a possible risk that the client continues to send this message without a stop. So I would like to propose the following change: s/ " If both MRC and MRD are zero, the client continues to transmit the message until it receives a response." / "The client must be informed with a limit of its retransmission behavior, and MUST NOT set both MRC and MRD to zero" -zhen