> Assume if PRACK is sent in this scnario , > the offer/answer will be different, as SDP body > in the PRACK is optional , and if a SDP body > is sent in the PRACK then the immediate > response of that PRACK must contain an answer.
There is no difference within my answer. Per rfc3261, the SDP within the INVITE 2xx must be ignored; it is not an offer. Concerning my earlier comment "assuming PRACK used but not shown", I was trying to indicate that SDPs within 18x, UPDATE, and UPDATE 2xx are not offers and answers (or trigger UPDATE failure responses). This is because of the rfc3261 requirement that 18x with SDP is not an "answer" unless it is sent reliably. > For Eg: > > INVITE (Offer1) > 18x (Answer1) > PRACK (Offer) > 2xx PRACK (Answer) > UPDATE (Offer2) > 2xx UPDATE (Answer2) > 2xx INVITE (Offer3) /* This will be a new offer again */ > ACK INVITE (Answer3) > > Thanks and Regards, > Geetha > --- Brett Tate <[EMAIL PROTECTED]> wrote: > > > > To my understanding , > > > In the scenario mentioned by you. > > > INVITE (Offer1) > > > 18x (Answer1) > > > UPDATE (Offer2) > > > 2xx UPDATE (Answer2) > > > 2xx INVITE (Offer3) /* This will be a new offer > > again */ > > > ACK INVITE (Answer3) > > > > > > So an answer for offer3 needs to be sent in ACK. > > > > Within your example (assuming PRACK used but not shown), the SDP > > within INVITE 2xx must be ignored. Thus it is not an > offer; and there > > would not be an answer within the ACK. _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
