I have reviewed this document as part of the security directorate's ongoing effort to review all IETF documents being processed by the IESG. These comments were written primarily for the benefit of the security area directors. Document editors and WG chairs should treat these comments just like any other last call comments. This draft specifies how the Session Initiation Protocol (SIP) can use the non-blocking version of the Interactive Connectivity Establishment (ICE) protocol, Trickle ICE, and defines a new registry for this usage. The security considerations section does exist and defers security concerns to draft-ietf-mmusic-ice-sip-sdp, RFC 6086, and draft-ietf-ice-trickle. 1. draft-ietf-mmusic-ice-sip-sdp This will hopefully be available for a secdir review in the near future, see general comments concern below. 2. RFC 6086 6086 prescribes S/MIME if the environment requires payloads to be private and also suggests a digest-challenge in order to provide integrity protection. 3. draft-ietf-ice-trickle defers to draft-ietf-ice-rfc5245bis. ice-sip should reference the 5245bis draft directly. I won't duplicate Stephen's efforts in reviewing 5245bis. General comments: I'm concerned about the normative references to ietf-mmusic-ice-sip-sdp. This draft should progress before or along with any dependents. Editorial comments: Some of the abbreviations that are not expanded and are not listed as well known by the RFC Editor: SDP AOR STUN TURN GRUU (needs to be expanded in Section 3.1) making it cumbersome to follow the specification. Shawn. --