I am the assigned Gen-ART reviewer for this draft. For background on Gen-ART, please see the FAQ at < http://wiki.tools.ietf.org/area/gen/trac/wiki/GenArtfaq>. Please resolve these comments along with any other Last Call comments you may receive. Document: draft-ietf-insipid-session-id-reqts-08.txt Reviewer: Elwyn Davies Review Date: 23 September 2013 IETF LC End Date: 24 September 2013 IESG Telechat date: (if known) - Summary: Amost ready with very minor issues/nits. The only issue that is of any consequence to my mind is handling of legacy B2BUAs etc. Major issues: None. Minor issues: s4.3: I am not clear whether there needs to be any special consideration if the B2BUA doesn't support Session-ID. There could be a number of other cases to consider. In particular whether the B2BUA would forward the Session-ID if it didn't understand it. Does this also affect SBCs? Nits/editorial comments: s1: The purpose of the document is not explicitly set out in s1 - although of course it is clear in the abstract. s1 should contain a near copy of the abstract which also states that the document proposes requirements for a new SIP header (I assume) called "Session-ID". s1, para 2: > This important fact makes it > impossible for call identifiers to be exchanged end-to-end when a > network uses one or more session protocols. I would have thought that using just one session protocol didn't give problems. Do you mean "... uses more than one session protocol."? s1, last para: Expand acronym PBX. s3.1, para 6: s/some constraint/some constraints/ [arguable!] s3.2, Figure 1: [very nitty] Might be desirable to indicate the existence of the middlebox(es) on the message arrows (e.g., .....()..... or some such). Also label A and B as user agents. s3.2, 4th bullet: s/(e.g., Alice and Bob)/(e.g., between Alice and Bob)/ s3.2, 5th bullet and sub-bullets: The 2nd sub-bullet is a bit confusing: Maybe: OLD: o A call between any two user agents wherein two or more user agents are engaged in a conference call via a conference focus o Each call between the user agent and the conference focus would be a communication session o Each communication session is a distinct communication session NEW o A call between any two user agents wherein two or more user agents are engaged in a conference call via a conference focus: o each call between the user agent and the conference focus would be a communication session, and o each of these is a distinct communication session. s3.2, 6th bullets and sub-bullets: Add periods (full stops) at end of each. s4.1: Acronyms UA, B2BUA and SBC need expansion (UA and B2BUA are effectively used in s1. SBC may need a reference (RFC 6135?) s4.1: Desirable to specify that "(SIP) dialog" is defined in s12 of RFC 3261. s4.2: Once you have expanded SBC in s4.1 you could use it in s4.2! s4.3, para 1: s/SIP users, device or domain identity./SIP users, device or domain identities./ s4.3, para 1: s/or when security issue arise (e.g./or when a security issue arises (e.g.,/ s4.7, para 1: s/between two or more parties./between two or more parties other than the one setting up the call./ s7, para 2: s/In adherence with/In adhering to/