> 1. UAS never sends 199: > > In this case only forking proxies/B2BUA > would send 199.
I prefer the goal of option 1. B2BUA (which is a UAS) or proxy sends 199 whenever it desires to indicate termination of a dialog and sending a final INVITE response is not yet appropriate. The subsequent INVITE final response SHOULD contain a different To tag than those sent within 199s. A device which does not trigger more than 1 To tag (i.e. fork or simulate forking interaction) for an INVITE, SHOULD NOT generate a 199 since it needs to generate subsequent final failure response with the same To tag. <snip> > Robert S also raised an issue on what Require: 199 means. It means the UAS is required to support the RFC. Depending upon RFC (working group decision), "Require: 199" means UAS MAY, SHOULD, or MUST send 199 for early dialogs containing To tags different than the INVITE's subsequent final response To tag; I prefer MAY. Depending upon RFC (working group decision), "Require: 199" also means UAS MAY, SHOULD, MUST, or SHOULD NOT send 199 for early dialog containing To tag which is the same as the INVITE's subsequent final response To tag; I prefer SHOULD NOT. If MUST is preferred, I would desire usage of a different option-tag such as "failure-reason" or "termination-reason". _______________________________________________ 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
