Dale, History-Info can provide some information, depending of course whether all proxies forward it and add to it as it goes downstream, that the UAS sends it back, and that all proxies forward it upstream in the response. It doesn't give you all the information you would get from your idea, of course. Both mechanisms would suffer from border elements that strip things out for topology hiding or other reasons.
On the detail, I believe 170 would establish an early dialog - is this desirable, and if not is it avoidable? John > -----Original Message----- > From: [email protected] [mailto:[email protected]] On > Behalf Of Dale Worley > Sent: 23 February 2009 21:37 > To: SIP > Subject: [Sip] Diagnostic idea > > I've been considering the following idea for a diagnostic > tool, and I'd > like to get some feedback on it. > > The goal is to be able to trace the progress of a SIP request through > the network, including seeing the forking structure. We first need to > pick a provisional response codes. It appears that "170" is not > currently used. This response code is also used as an option-tag for > this feature. The processing is that whenever a SIP element > receives a > request that contains "Supported: 170", the element will > immediately (in > addition to anything else that it would do with the request) > send a 170 > response upstream, containing the request as its body (media type > message/sipfrag). > > Dale > > > _______________________________________________ > Sip mailing list https://www.ietf.org/mailman/listinfo/sip > This list is for NEW development of the core SIP Protocol > Use [email protected] for questions on current sip > Use [email protected] for new developments on the application of sip > _______________________________________________ Sip mailing list https://www.ietf.org/mailman/listinfo/sip This list is for NEW development of the core SIP Protocol Use [email protected] for questions on current sip Use [email protected] for new developments on the application of sip
