Hi Tarun, According to the old saying "Be liberal with receiving and strict while delivering", B2BUA is doing best attempt to succeed the call.
Are you sure the BYE has come for intended Dialog? (Does the Call-Id, From-Tag, To-Tag match?). If BYE is catching 481, it means dialog matching rules has one more condition to check if From-Tag is not same as To-Tag which should have been checked well before accepting the call. Since B2BUA has accepted the call and now if its saying 481 for BYE, its problem with B2BUA :) Okay, now if B2BUA has to reject the call well before, it can do so by sending BYE towards UA2 (since UA2 has confirmed the dialogue) and 500 Internal Server Error towards UA1. Thanks, Somesh -----Original Message----- From: sip-implementors-boun...@lists.cs.columbia.edu [mailto:sip-implementors-boun...@lists.cs.columbia.edu] On Behalf Of ext Tarun2 Gupta Sent: Monday, June 04, 2012 9:07 AM To: sip-implementors@lists.cs.columbia.edu Subject: [Sip-implementors] Same tags in To and From headers in 200 OKresponse Hi All Consider the following scenario: UA 1 B2BUA UA2 Invite (From tag F1) ---------------------------------> Invite (From tag F2) ----------------------------------> 200 OK (From tag F2, To tag F2) <--------------------------------- 200 OK (From tag F1, To tag F3) <------------------------------- ACK (From tag F1, To tag F3) -------------------------------> ACK (From tag F2, To tag F2) ----------------------------------> RTP <------------------------------------------------------------------> BYE (From tag F2, To tag F2, To and From headers reversed) <---------------------------------- 481 ----------------------------------> As per Section 19.3 of RFC 3261, "When a tag is generated by a UA for insertion into a request or response, it MUST be globally unique and cryptographically random with at least 32 bits of randomness" Now, is the B2BUA right in rejecting the BYE with a 481. Can the 200 ok from UA2 have same To and From tags? What should the B2BUA do: 1. On receiving the 200 OK? 2. On receiving the BYE? Regards, Tarun Gupta Aricent ======================================================================== ======= Please refer to http://www.aricent.com/legal/email_disclaimer.html for important disclosures regarding this electronic communication. ======================================================================== ======= _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
