But if a proxy does not support 3326, then it should Forward the header instead of not including the Reason header. Else the whole purpose of adding the Reason header would be lost!!
Regards Ranjit -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Bob Penfield Sent: Monday, February 09, 2009 6:09 PM To: Iñaki Baz Castillo Cc: [email protected] Subject: Re: [Sip-implementors] "Reason-Header" inCANCELthroughvariousproxies RFC 3261 section 9.1 defines how CANCEL requests are constructed. Section 16.10 talks about how a proxy processes a CANCEL request refers to section 9.1. Section 16.6 (Request Forwarding) does not apply to CANCELs in a stateful proxy. IMO, a strict interpretation of these sections would prevent a proxy from blindly copying all headers from the received CANCEL into the outgoing CANCEL. However, new RFCs, which build on 3261 and define new headers that can appear in a CANCEL request, can define proxy behavior for processing those headers. RFC 3326 does in fact does define proxy behavior for the Reason header. On page 3 it states: Proxies generating a CANCEL request upon reception of a CANCEL from the previous hop that contains a Reason header field SHOULD copy it into the new CANCEL request. So a proxy which supports 3326 should include the received Reason header in the CANCELs that it sends. However, User Agents cannot rely on this behavior because proxies that do not support 3326 will likely not include the Reason header in CANCELs they send. Cheers, (-:bob -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Iñaki Baz Castillo Sent: Monday, February 09, 2009 7:14 AM Cc: [email protected] Subject: Re: [Sip-implementors] "Reason-Header" inCANCELthroughvariousproxies 2009/2/9 Attila Sipos <[email protected]>: >>>Yes, in fact I hope you are right :) > > I do too!! > > I worry that one of the SIP heavyweights is going to correct me ( it's > happened before!! ) > > I'm sure they will add something to clarify! Let's wait for them :) -- Iñaki Baz Castillo <[email protected]> _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
