The answer is no. If X is 183, you can not send re-invite to UA as previous offer-answer is not complete and there is no dialog established to send re-invite. You can send update on early dialog instead of re-invite but this will have inter-operation issues and this also means that 183 needs to be reliable. Why not send another another 183 instead of re-invite towards UA? This 183 needs to have different to-tag than the first one. Basically, UA will assume that its invite got forked to two end-points. But again, some UA will ignore this second 183 and continue to use the first 183 leading to inter-operation issues. My best advice is to continue with this call-flow.
On Tue, Jul 15, 2008 at 8:35 PM, <[EMAIL PROTECTED]> wrote: > Dear community, > > I have a question regarding MRF, that runs a sequence of VXML-scripts > > User agent A SIP-Proxy SIP-AS MRF > !---invite----------------->! ! ! > ! !--------invite------->! ! > ! !<------invite---------! ! > ! !--------invite---------!---------------->! > ! !<-----OK------------!-------------------! > ! !--------OK--------->! ! > ! !<-------OK----------! ! > !<------ X ----------------! > !------ACK-------------->!---------ACK------->! ! > ! !<-------ACK--------! > ! !--------ACK---------!----------------->! > > ==== RTP-Stream, A talking to MRF ==== > > MRF sends a BYE to SIP-AS via SIP-Proxy, the result of the dialogue > Is contained within the subject-header of the BYE message: > ! !<----------------------!----BYE---------! > ! !----BYE----------->! ! > SIP-AS sends OK back to MRF via SIP-Proxy: > ! !<--OK---------------! ! > ! !------OK--------------!------------------->! > > So the leg between MRF & SIP-AS does not exist any more. > SIP-AS uses the result of the dialogue to perform some action > SIP-AS decides to start another VXML-dialogue to A > ! !<---invite-------------! ! > ! !-----invite-------------!-------------------->! > > MRF answers with 200OK via SIP-Proxy: > ! !<-------------OK-------!----------------------! > ! !-------OK------------->! ! > > Now SIP-AS (re)invites A: > ! !<--invite----------------! ! > !<---inivte--------------! > A answers with 200OK, A and MRF can talk - I did not draw this too.. > > My question is now: > If X would be a 183 session progress instead of 200OK, > (and no ACK is sent back to MRF), can the callflow contiune as described ? > > >From A this happens: > A sends an invite, receives a provisional response, is waiting and then > receives a reinvite. > Is this possible ? > > Is there a RFC ? > > Best regards, > > Frank Niedermueller > > [EMAIL PROTECTED] > > > > > > _______________________________________________ > 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
