Approach 2 is preferred User A waits for 1XX from User B and then send a CANCEL.
See Section 9.1, page 54 of RFC3261. "Once the CANCEL is constructed, the client SHOULD check whether it has received any response (provisional or final) for the request being cancelled (herein referred to as the "original request"). If no provisional response has been received, the CANCEL request MUST NOT be sent; rather, the client MUST wait for the arrival of a provisional response before sending the request." Thanks, Neel -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Kavita Rai Sent: Friday, March 24, 2006 6:56 AM To: 'Sip-Implementors' Cc: Seshu; Ajay Prakash; Kavita Rai Subject: [Sip-implementors] Call Termiantion Prior to Receiving 1xx Need help on following Scenario: If User A initiated a call to user B, and user A decides to disconnect the call before it has received a 1xx response, how should the call termination proceed?? I can think of these 2 approaches but am not sure which one to follow: 1) The user A cannot send Cancel since 1xx hasn't been received.Hence decides to clear the call at its side. The terminating side sends a 1xx, 2xx and user B eventually times out. 2) User A waits for the 1xx from user B and then sends a Cancel to user B or waits for a transaction timeout of Invite to clear the call. Would appreciate any inputs on this. Regards, Kavita [EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]> _______________________________________________ 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
