Hi, the answer to your question "whether an ACK should be send after the 487 is received or not"? is if 487 is received, you MUST send ACK. Other wise, since 2543 complaint UAS will not send a 487 for the original requests after getting CANCEL, UAC can not reply on it. What RFC says in these situations is "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."
rgds, Prince "modulino" <[EMAIL PROTECTED]> Sent by: [EMAIL PROTECTED] 04/22/2005 03:01 PM To <[email protected]> cc Subject Re: [Sip-implementors] Doubt regarding the Cancelling of a Request... > Hi, > > When any Request has been Terminated by sending CANCEL Msg a 487 Msg is > generated in response to that. My doubt is, whether an ACK should be send > >after the 487 is received or not. Hi, the UAC must ACK any final response received for the INVITE request. The ACK for a non-2xx final response is generated by the transaction layer, while the ACK for a 2xx response is generated by the UAC core (because the 2xx terminates the client transaction). _______________________________________________ Sip-implementors mailing list [email protected] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors *********************** FSS-Private *********************** _______________________________________________ Sip-implementors mailing list [email protected] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
