"Karthik.v" <karthik...@plintron.com> writes: > 1) You meant to say that Registration is creating a dialog (dialog-id) but > there is no reason for using it. Am I correct ?
A registration does *not* create a dialog, but the stream of REGISTER messages has some of the properties of a dialog, in particular, they share the same Call-Id. If the REGISTER messages *did* create a dialog, it would not have much use, because calls cannot be sent to the UA on it. > 2) No more thing is here, can u explain me the logical reason behind "The > Contact header field MUST contain exactly one SIP > or SIPS URI in any request that can result in the establishment of a > dialog" ? If the other UA in the dialog wants to send a request to the initial UAC, it uses the URI from the Contact of the first request as the request-URI. (That is because the Contact URI becomes part of the "route set" of the dialog that is recorded by the initial UAS. The route set is used by that UA to construct requests within the dialog. The details are given in RFC 3261.) Dale _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
