Please see attached review. Brian 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-hanes-dispatch-fax-capability-06.txt Reviewer: Brian Carpenter Review Date: 2012-12-05 IETF LC End Date: 2012-12-27 IESG Telechat date: Summary: Almost ready -------- Comment: Clear, easy to understand -------- Minor issue: ------------ ... A UA preferring the reception of fax calls MUST include the "sip.fax" media feature tag in the Contact header field of REGISTER messages. To confirm the registration of this preference, a SIP [RFC3261] Registrar MUST then include this tag in the Contact header field of its 200 OK response. If the Registrar does not do this (e.g. because it hasn't been updated to support the new tag), what does the UA do when it receives the 200 OK response that doesn't include the tag?