Let me try to answer this question: Alex Zhang ESN: 6-554-8782
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of JEEVANANDHAM KARTHIC KUMAR Sent: Friday, April 11, 2008 2:49 PM To: [email protected] Subject: [Sip-implementors] Query:CANCEL for UPDATE request Hello, I have confusion to cancel the UPDATE request and INVITE. Please consider the following scenario. UAC UAS ------------INVITE(SDP)-------> <-----------100 Trying-------- <-----------183 ( SDP))------- ------------PRACK------------------> <------------200 OK(PRACK)----- --------------UPDATE(SDP)-------> Now UAC want to terminate the session. What message UAC Should send to UAS? [ALEX] CANCEL message. Note: A CANCEL request SHOULD NOT be sent to cancel a request other than INVITE. one CANCEL message is enough or It should send CANCEL for UPDATE and then CANCEL for INVITE. [ALEX] I think the UPDATE will be rejected by the non-2xx message (update). Similarly , the initial Invite will also be rejected by another non-2xx message (Invite). In UAS side, If UAS receive CANCEL request, how it will identify whether the CANCEL for INVITE or UPDATE. [ALEX] The Request-URI, Call-ID, To, the numeric part of CSeq, and From header fields in the CANCEL request MUST be identical to those in the request being cancelled, including tags. the same problem may happen for cancelling PRACK also. Could you please give your view on this. Reagrds, karthic kumar J _______________________________________________ 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
