Hi, > 1. As per RFC 3261, a 101-199 response may or may not contain a "To" tag. > Section 13.2.2.1 of RFC 3261 says the following: > > " The early dialog will only be needed if the UAC needs to send a > request to its peer within the dialog before the initial INVITE > transaction completes." > > Since PRACK to 101-199 is sent before the INVITE transaction completes, does > this mean that, to support the Reliable Provisional Response RFC (RFC 3262), > the 101-199 responses MUST always contain the To tag?
[CHH] Yes. > 2. The second query is related to error response to PRACK. What is the > meaning of 3xx-6xx response to PRACK? If a PRACK receives a 3xx-6xx > response, what should happen to the INVITE transaction? [CHH] It's an implementation specific issue. You can choose to accept it, not to accept it, or release the session setup. > 3. If a UAC receives a 2xx to INVITE before receiving 2xx to a PRACK, should > the UAC accept the 2xx to INVITE? > > UAC UAS > > ----- INVITE -------------> > > <------ 180 -------------- > ------- PRACK -----------> > > <------- 2xx (INVITE) ------ > > Should the 2xx to INVITE be accepted in the above case? [CHH] Chapter 5 of RFC3262 talks about the UAS not sending the 200 (INVITE) if it has a pending reliable18x *WITH* SDP (I have some issues with that rule, but that's another discussion...), but I don't think the spec says anything about how the UAC shall behave if it receives 200 (INVITE) before 200 (PRACK). In fact, I think that will be a pretty normal scenario, and will for example occur every time the UAS sends 200 (INVITE) before it has received PRACK for a pending reliable 18x (without SDP). Regards, Christer Holmberg Ericsson Finland > > > Regards, > Udaya > > _______________________________________________ > Sip-implementors mailing list > [EMAIL PROTECTED] > http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors _______________________________________________ Sip-implementors mailing list [EMAIL PROTECTED] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
