See following sentences from 3261. Note that both the transaction corresponding to the original request and the CANCEL transaction will complete independently. However, a UAC canceling a request cannot rely on receiving a 487 (Request Terminated) response for the original request, as an RFC 2543- compliant UAS will not generate such a response. If there is no final response for the original request in 64*T1 seconds (T1 is defined in Section 17.1.1.1), the client SHOULD then consider the original transaction cancelled and SHOULD destroy the client transaction handling the original request.
-------------------------------------------------- From: "Klaus Darilion" <[EMAIL PROTECTED]> Sent: Friday, March 07, 2008 5:10 PM To: <[email protected]> Subject: [Sip-implementors] CANCEL retransmisson question of no provisionalresponse! > Hi! > > Could someone help me please with this question. > > Scenario: A transaction-stateful proxy forwards the INVITE request. The > proxy does not receive a provisional response, thus starts > retransmissions. Now, the caller CANCELs the call. How is the proxy > supposed to handle this? Does the proxy still have to retransmit the > INVITE or can it stop retransmitting the INVITE? > > From logical point of view I would think that the proxy should stop the > retransmissions, but from Figure 5 in RFC 3261 it looks like the only > way to come from "Calling" state to "Terminated" state is waiting for > Timer B fires (as there is no provisional response yet). > > thanks > klaus > _______________________________________________ > 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
