This review is intended for the use of the Operations Area directors. 


Please treat the comments like any other Last Call comments.




Tom Taylor



Summary: This document changes details of protocol for a specific SIP 


method. Provision is made for interworking between updated and older 


versions of the protocol, allowing incremental deployment of updated 


software. (At the protocol level, the absence of a GRUU in the 


signalling can be interpreted in more than one way, but the proposed 


interpretation in this document combined with the provisions of 


draft-ietf-sipcore-6665-clarification give a reasonable result.) That 


said, the document contains no text explicitly addressing operational or 


management issues.






The document is good to go except that IDNits complains about an 


outdated reference.