Yes should be possible , but you may need to do do a fresh offer/answer exchange on receipt of 200 OK because you might have been playing the media/ringback from a different UAS than the one which generated the 200 OK because of forking downstream. Check out RFC 3959 and 3960 ... Regards , Sayan
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Thursday, January 20, 2005 12:51 PM To: [EMAIL PROTECTED]; [EMAIL PROTECTED]; [EMAIL PROTECTED]; [email protected] Subject: RE: [Sip-implementors] why 180 and 183 come back togather? Yes! But if 183 is with SDP information, Originator will hear ring back played by remote end. Let us assume the case when two 180 responses are reaching to originator. Is it possible that originator, who was listening ring back tone for first 180 response, would start talking to 2nd phone on receiving 200 Ok (assuming first forked invite was canceled by the proxy)??? Vivek -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Chowdhury, Sayan (Sayan) Sent: Thursday, January 20, 2005 11:44 AM To: [EMAIL PROTECTED]; 'Laura Meng'; [email protected] Subject: RE: [Sip-implementors] why 180 and 183 come back togather? may be due to early media as well , with the second ring back being played back by the remote end/pstn gateway , as Ben says , without the full scenario it's not possible to know exactly what causes this . IMHO , you should not really be playing a local ring back on receipt of an 183 .. 183 is just session progress , not really meant to start of a local ring back ... -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Franz Edler Sent: Thursday, January 20, 2005 9:56 AM To: 'Laura Meng'; [email protected] Subject: RE: [Sip-implementors] why 180 and 183 come back togather? From: Laura Meng Sent: Wednesday, January 19, 2005 1:59 PM > double ringback, it seem one from 180, another from 183, but why this two > response occure togather? is it because the proxy fork INVITE to a PSTN > phone as well as IP phone? Yes, this is due to forking. > if so, should the proxy forward all the 180/183 back? Yes. > if so, what a mass at the UA's end, it start a single phone to want > to talk to someone, but turn out maybe it could get a meeting there! In case of the first final response arriving at the forking proxy this proxy must cancel all other pending transactions. So in normal forking case the UAC will get more 18x responses but only one 200 (RFC 3261 16.7-10). I hope that helps Franz _______________________________________________ Sip-implementors mailing list [email protected] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors _______________________________________________ Sip-implementors mailing list [email protected] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors Confidentiality Notice The information contained in this electronic message and any attachments to this message are intended for the exclusive use of the addressee(s) and may contain confidential or privileged information. If you are not the intended recipient, please notify the sender at Wipro or [EMAIL PROTECTED] immediately and destroy all copies of this message and any attachments. _______________________________________________ Sip-implementors mailing list [email protected] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
