Hi But u use re-invite to change the session parameters of an existing call. So how can u send CANCEL then?
Ranjit ----- Original Message ----- From: Robert Sparks <[EMAIL PROTECTED]> To: Ranjit Avasarala <[EMAIL PROTECTED]> Cc: Suresh Arora <[EMAIL PROTECTED]>; Medhavi Bhatia <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]> Sent: Thursday, July 18, 2002 3:12 PM Subject: [Sip-implementors] Re: [Sip] CANCEL FAQs > > On Thu, 2002-07-18 at 13:34, Ranjit Avasarala wrote: > > u cannot send CANCEL for re-invite as u won't be getting any ringing tone as > > response > > This is not correct. > > If you have received a provisional response, you can, in fact, send > a CANCEL to a re-INVITE. However, the nature of re-INVITE is such > that it is not likely to pend for long, so the chances that the CANCEL > won't arrive in time to affect the re-INVITE are higher than they are > for an initial INVITE. > > > > > > Ranjit > > ----- Original Message ----- > > From: Suresh Arora <[EMAIL PROTECTED]> > > To: Medhavi Bhatia <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]> > > Sent: Wednesday, July 17, 2002 6:14 PM > > Subject: RE: [Sip] CANCEL FAQs > > > > > > > I think UAS can send CANCEL to UAC for a re-INVITE (if requested session > > > characteristics are not supported by Server). > > As Ajit already pointed out, if the UAS doesn't like an INVITE request > it sends a response, not another request. CANCEL works like this: > > INVITE > --------> > CANCEL > --------> > > NOT like this: > > INVITE > --------> > CANCEL > <-------- > > For the case you call out (unsupported session characteristics) the > UAS will return a 488 (or possibly a 606). Thus: > > INVITE > --------> > 488 > <-------- > > > > > > > -Suresh > > > > > > -----Original Message----- > > > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Medhavi > > > Bhatia > > > Sent: Wednesday, July 17, 2002 9:21 AM > > > To: [EMAIL PROTECTED] > > > Subject: Re: [Sip] CANCEL FAQs > > > > > > > > > This stuff generally belongs to the implementor's list: sip-implementors > > > <[EMAIL PROTECTED]> > > > > > > Generally CANCEL should not be used for transactions which are bound to > > > complete > > > quickly, and never for transactions for which you havent received a > > > provisional (1xx) > > > response. So the answer for (1) would be: probably not. Also the UAS > > cannot > > > cancel > > > a transaction started by the UAC (I guess that's what you meant), so it > > > cannot generate > > > the CANCEL ever. > > > > > > ----- Original Message ----- > > > From: "Sp.Raja" <[EMAIL PROTECTED]> > > > To: <[EMAIL PROTECTED]> > > > Sent: Tuesday, July 16, 2002 6:25 AM > > > Subject: [Sip] CANCEL FAQs > > > > > > > > > > Please help me out by answering these questions. > > > > > > > > 1. Can CANCEL be used to cancel a bye ? > > > > > > > > 2. Can CANCEL be send by the called entity (UAS) ? If yes then under > > what > > > > circumstances > > The answers above probably address what you meant, but to be > complete: > > The "called entity" plays the role of a UAS for the transaction > processing the INVITE it received. It cannot CANCEL that transaction, > it can only send responses in it. > > If that INVITE is accepted, the called entity can later send > its own requests (such as (re-)INVITE). It is playing the roal > of a UAC for those request transactions, and once it recieves > a provisional response, it can send CANCELs. > > RjS > > > > > > > > - Sp.Raja > > > > > > > > > > > > > _______________________________________________ > > > Sip mailing list https://www1.ietf.org/mailman/listinfo/sip > > > This list is for NEW development of the core SIP Protocol > > > Use [EMAIL PROTECTED] for questions on current sip > > > Use [EMAIL PROTECTED] for new developments on the application of sip > > > > > > > > > > > > _______________________________________________ > > > Sip mailing list https://www1.ietf.org/mailman/listinfo/sip > > > This list is for NEW development of the core SIP Protocol > > > Use [EMAIL PROTECTED] for questions on current sip > > > Use [EMAIL PROTECTED] for new developments on the application of sip > > > > > > _______________________________________________ > > Sip mailing list https://www1.ietf.org/mailman/listinfo/sip > > This list is for NEW development of the core SIP Protocol > > Use [EMAIL PROTECTED] for questions on current sip > > Use [EMAIL PROTECTED] for new developments on the application of sip > > > _______________________________________________ > 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
