On Tue, 2009-03-31 at 16:28 +0300, Neranza Bundova wrote: > I would like to ask a question regarding semi-attended transfer > described in draft-ietf-sipping-cc-transfer-12. The Transferor waits > receiving of 2xx response from the transfer target before to continue > the transfer. What if the transfer target hasn't sent 2xx response in a > day? How the transferor can terminate the transfer because too long time > has passed?
It is implicit in SIP (but I do not know if it has been written down) that if a request has been sent but a response has not been received in too long, then there is an implicit 408 response generated in the UAC internally by the SIP stack. So the transferee (the one that receives the REFER) should consider the INVITE to have received a 408 response within (I believe) 3 minutes, and should report the 408 response to the transferor (the sender of the REFER) in a NOTIFY. If the transferee doesn't do this, the transferor can simply give up on the transfer. Sending the REFER doesn't terminate the original dialog (until the transferee gets a 2xx response to the stimulated INVITE, at which point the transferee will send a BYE on the original dialog). So the transferor can continue with the original dialog. Dale _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
