Hi , 1) UAC has sent an INVITE request with header Supported: 100rel and also with SDP offer 2) UAS sends a reliable provisional response with 180 Ringing with Require: 100rel and also with SDP answer 3) But before even receiving PRACK by UAS for above step , UAS sends a final failure 4xx response towards UAC 4) UAC has sent the ACK for that Final failure 4xx response. 5) Now after all PRACK has been sent by UAC for that reliable provisional response of step 2 6) UAS is not sending any response for that PRACK request. So what should be the expected behavior of UAS? As per RFC 3262 The UAS MAY send a final response to the initial request before having received PRACKs for all unacknowledged reliable provisional responses, unless the final response is 2xx and any of the unacknowledged reliable provisional responses contained a session description. In that case, it MUST NOT send a final response until those provisional responses are acknowledged. If the UAS does send a final response when reliable responses are still unacknowledged, it SHOULD NOT continue to retransmit the unacknowledged reliable provisional responses, but it MUST be prepared to process PRACK requests for those outstanding responses. A UAS MUST NOT send new reliable provisional responses (as opposed to retransmissions of unacknowledged ones) after sending a final response to a request. But even after sending failure a final response and receiving an ACK for that, Still UAS has to send some response for that message?
Thanks,Sourav _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
