Dear Ivar, Transaction User for B2BUA or UAS/UAC separately, could be defined as Dialog and above it can be application Layers.
RFC does not clearly define this ( as for stateless proxy case there is no dialog/session kind of thing, so RFC keeps TU detail a bit generic by refer it as UAC/UAS core ). RFC-3261 just splits the layer into UAC core/UAS core running ontop of transaction layer. Now UAC core/UAS core could contains dialog functionality and thus can provide the 200 OK retransmission/timeout handling on the UAS side and ACK for duplicate 2XX on the UAC side based on t1 and t2 timer value ( section 13.2.2.4, page 82, 83, section 17 page 122, 123, 124 third para ) Regards, Indresh K Singh ------------------------------------------------------------- Sr. Software Engineer SIP Media Control and Signaling Nokia Siemens Networks Boca Raton, FL-33487 Ph: 561-923-5085 (o), 561-923-2048 (o) ------------------------------------------------------------- >>-----Original Message----- >>From: ext Ivar [mailto:[EMAIL PROTECTED] >>Sent: Tuesday, May 15, 2007 4:25 PM >>To: Singh, Indresh (SNL US); [email protected] >>Subject: RE: [Sip-implementors] ACK and UAS dialog >> >>I have read 12-19, >> >> >>I know that positive response ends transaction. >>Ok what is transaction user for b2bua ? >> >>I'm trying to figgure out if its possible and wise to handle >>ack in dialog. Like uac dialog sends ack and uas dialog does >>retransmission of positive response while gets ack or 64x t2 reached. >> >>If that's not allowed or wise, there may n calls at same >>time, what normal way to map timer to dialog. >> >> >> >> >>-----Original Message----- >>From: "Singh, Indresh (SNL US)" <[EMAIL PROTECTED]> >>To: "ext Ivar" <[EMAIL PROTECTED]>; [email protected] >>Sent: 05/15/2007 23:17 >>Subject: RE: [Sip-implementors] ACK and UAS dialog >> >>Hi Ivar, >>Hi Ivar, >> >>I would recommend referring to section-12 ( dialog ) section >>13 (session >>) and section 17 ( transaction ) collectively of RFC-3261 for case >>described below. >> >>Yes the UAS created dialog should wait for the ACK, otherwise TU ( >>Transaction User ) running a 2xx timer waiting for ACK should timeout >>and release the call by sending a BYE or fall-back to previous >>successfully negotiated media ( if it was for re-INVITE-200OK ). >> >>For 2XX case please note that the transaction becomes free, >>so it is the >>TU which is running the retransmission and timeout timers. >> >>Regards, >> >>Indresh K Singh >>------------------------------------------------------------- >>Sr. Software Engineer >>SIP Media Control and Signaling >>Nokia Siemens Networks >>Boca Raton, FL-33487 >>Ph: 561-923-5085 (o), 561-923-2048 (o) >>------------------------------------------------------------- >> >> >> >>>>-----Original Message----- >>>>From: [EMAIL PROTECTED] >>>>[mailto:[EMAIL PROTECTED] On Behalf >>>>Of ext Ivar >>>>Sent: Tuesday, May 15, 2007 11:02 AM >>>>To: [email protected] >>>>Subject: [Sip-implementors] ACK and UAS dialog >>>> >>>>Hi, >>>> >>>>After reading RFC 3261, i don't find place what describes following: >>>> >>>>UAC send INVITE, UAS gives 200 ok answer. >>>> >>>>Now UAC send ACK (thats nicely in rfc 13.2.2.4), where ACK is >>>>handled in >>>>UAS ? >>>>Does UAS created dialog must wait for ACK confirmation, if >>it doesn't >>>>get it, dialog will be terminated and BYE is sent to UAC ? >>>> >>>> >>>>_______________________________________________ >>>>Sip-implementors mailing list >>>>[email protected] >>>>https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors >>>> >> >> _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
