Iñaki Baz Castillo wrote: > 2009/3/4 hanifa.mohammed <[email protected]>: >> Hi all, >> >> an excerpt from rfc 3261: >> if the response for a request within a dialog is a 481 (Call/Transaction >> Does Not Exist) or a 408 (Request Timeout), the UAC SHOULD terminate the >> dialog. A UAC SHOULD also terminate a dialog if no response at all is >> received for the request (the client transaction would inform the TU about >> the timeout.) For INVITE initiated dialogs, terminating the dialog consists >> of sending a BYE. >> >> Is it necessary to send a BYE request out to the network? Bcoz, it is >> obvious that it will also get the same resp. cant UAC simply clean the local >> resource and inform the user that the dialog is closed. > > There is nothing wrong in sending the BYE even if most probably it > won't arrive to the UAS.
I think the requirement is more strong that just "nothing wrong". The only way UA can end established dialog is by sending BYE. The RFC is very specific that no other request or response does it. Therefore, sending BYE is required even in the cases when it seems to make no sense, like in this one. In practice, in complex network, there could be some call-stateful elements involved in the call (B2BUAs), so that sending BYE will ensure that those elements are properly notified about the intent of the UA to tear down the dialog. Regards, -- Maksym Sobolyev Sippy Software, Inc. Internet Telephony (VoIP) Experts T/F: +1-646-651-1110 Web: http://www.sippysoft.com MSN: [email protected] Skype: SippySoft _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
