Thanks all for the information, I should have included the callflow in the original message. |628.190 | INVITE SDP ( g729 telephone-event) | |(5060) ------------------> (5060) |628.190 | 100 Trying | |(5060) <------------------ (5060) |639.480 | 183 Session Progress SDP ( g729) | |(5060) <------------------ (5060) |647.015 | 200 OK SDP ( g729) | |(5060) <------------------ (5060) |647.040 | BYE | |(5060) ------------------> (5060) |648.354 | 200 OK SDP ( g729) | |(5060) <------------------ (5060) |650.358 | 200 OK SDP ( g729) | |(5060) <------------------ (5060)
As you can see the UAC never sends an ACK. The UAC vendor has confirmed this is due to the contents of the SDP received in the 200 OK. The consensus seems to be that the UAC is "clearly broken". The UAS eventually sends a BYE after a number of retransmissions. The case where the ACK and BYE are reversed in transit is interesting. If the UAS receives BYE then ACK would the UAS state machine transition to the Confirmed/Established state and rely on a retransmission of the BYE from the UAC to terminate the dialog? Thanks, Greg On Mon, Dec 29, 2008 at 4:00 PM, Kanumuri, Sreeram <[email protected]>wrote: > I agree there Must be ACK for Invite. > What I mean is the "UA that receives Bye" should be prepared to accept the > Bye and process it. > > You are referring the "UA that sends BYE" that it should send ACK > I am referring the "UA that receives BYE". > > Thanking you, > > Regards, > Sreeram. > > > > -----Original Message----- > From: Maxim Sobolev [mailto:[email protected]] > Sent: Monday, December 29, 2008 1:43 PM > To: Kanumuri, Sreeram > Cc: Greg Burrow; [email protected] > Subject: Re: [Sip-implementors] BYE in Confirmed/Moratorium state (RFC > 5407) > > Kanumuri, Sreeram wrote: > > Both cases are possible. So the UA MUST be ready to accept > > -ACK followed by Bye > > -only Bye (think of a race condition) > > I disagree with the latter. It should be "BYE followed by ACK", not just > "only BYE". Don't sending ACK at all would violate RFC causing > unnecessary retransmits of 200 OK. INVITE transaction (ACK is part of > which) completes independently and should not be affected by the dialog > state change due to the BYE. > > 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
