RFC6337, 2.3. Rejection of an Offer When a UA receives a PRACK request with an offer that it cannot accept, it may respond with a 200 response with a syntactically correct session description. Optionally, this may be followed by an UPDATE request to rearrange the session parameters if both ends support the UPDATE method. Alternatively, the UA may terminate the dialog and send an error response to the INVITE request (Pattern 5).
2012/7/12 Kamini Gangwani <[email protected]> > Hi Brett, > > Thanks a lot for resolving my queries. > As per RFC 6337, PRACK should be responded with 200 OK response followed > by termination of dialog and for dialog termination, sending 487 Request > Terminated would be the correct response and sending BYE would not be a > correct way. > > Thanks, > Kamini > > -----Original Message----- > From: Brett Tate [mailto:[email protected]] > Sent: Wednesday, July 11, 2012 5:56 PM > To: Kamini Gangwani; [email protected] > Subject: RE: Query regarding PRACK offer rejection > > Hi Kamini, > > Reply inline. > > > RFC 6337 says: > > 5. PRACK Req. (**) 200 PRACK Resp. followed by new offer > > OR termination of dialog > > > > If offer in PRACK is rejected then UAS should respond > > with 200 OK followed by BYE(i.e. termination of dialog) > > or new offer. > > If the termination of early dialog is done by receiver of the PRACK, it is > not done by sending BYE. It is done by sending an INVITE failure response > such as 487. > > > > Let say, we opt for terminating the dialog. > > <snip> > > > Is this the correct behavior to implement or should > > we reject only PRACK and dialog should not get impacted? > > If you follow the RFC 6337's recommendation, you cannot reject the PRACK. > > However if you reject PRACK with 488 (per the RFC 6337 open issue), it > might allow the dialog to remain or it might cause the UAC to release the > call or dialog (per their RFC 3262 interpretation or because they prefer to > CANCEL the INVITE or BYE the specific early dialog). > > The following is one of many threads discussing the 488 open issue. > > http://www.ietf.org/mail-archive/web/sipping/current/msg15146.html > > > The following is the RFC 6337 "**" text highlighting the hope that you > will not have to reject a PRACK's offer. > > "(**) A UA should only use PRACK to send an offer when it has > strong reasons to expect the receiver will accept the offer." > > > > > > > =============================================================================== > Please refer to http://www.aricent.com/legal/email_disclaimer.html > for important disclosures regarding this electronic communication. > > =============================================================================== > > _______________________________________________ > Sip-implementors mailing list > [email protected] > https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors > -- msn:[email protected] _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
