You can probably use the blackhole sdp mechanism for offer-answer exchange in SDP and setup the Invite dialog. But as Paul mentioned earlier, there will be no interoperability with other implementations.
Sanjay >-----Original Message----- >From: [EMAIL PROTECTED] >[mailto:[EMAIL PROTECTED] On >Behalf Of Vikram Chhibber >Sent: Thursday, November 15, 2007 4:58 PM >To: Paul Kyzivat (pkyzivat) >Cc: sip-implementors@lists.cs.columbia.edu >Subject: Re: [Sip-implementors] page-mode instant-messaging question > >I strongly feel that IETF should define a standard where >media-description is defined to propagate SIP MESSAGE as session-mode. >This way small applications like synchronization of some part >of my address boob with peer etc. can be developed where MSRP >will be an overkill and page-mode messaging may have >performance impact on the network. >Any opinion on this? > >On Nov 15, 2007 7:40 PM, Paul Kyzivat <[EMAIL PROTECTED]> wrote: >> >> >> ???? wrote: >> > Hi, >> > I am not sure of your use case but I think your >requirement could be achieved if you send INVITE/ACK without >any content (SDP media or something else). This will make >session hence end-to-end dialog for you. >> >> I beg to differ. If you send the INVITE without any content >then it is >> an offerless invite. In that case the UAS is obligated to send an >> offer in its response. >> >> Of course it *could* send an offer with no media, but most UAs would >> offer media in that case. And of course if it did offer you >media you >> could accept the call but refuse the media, which would >arrive at the >> same place that sending an offer with no media would. >> >> But if you intent going in is to establish a call with no >media, then >> you are better off being explicit about it. Take a case >where the call >> is forked to devices with different capabilities - e.g. a phone that >> only does voice as well as a device that does this >> session-mode/page-mode thing. If you make your offer then the phone >> can refuse the call. If you make an offerless invite then it >will most >> likely respond. >> >> Paul >> >> >> > Vipul Rastogi >> > Engineer, Business Management Team >> > Telecommunication Network Business >> > Samsung Electronics CO, LTD >> > Suwon P.O.BOX 105, 416 >> > Korea 442-600 >> > MO 010-9530-0354 >> > ----- Original Message ----- >> > From: "Vikram Chhibber" <[EMAIL PROTECTED]> >> > To: <sip-implementors@lists.cs.columbia.edu> >> > Sent: Wednesday, November 14, 2007 11:15 PM >> > Subject: [Sip-implementors] page-mode instant-messaging question >> > >> > >> >> Hi, >> >> >> >> I want to perform page-mode instant messaging (using SIP MESSAGE) >> >> on a dialog created by INVITE. This INVITE I want for >establishing >> >> a dialog on which I can send SIP MESSAGE only and there >will be no >> >> media. I do not want msrp either. >> >> In this case, how should I construct offer and then answer SDP? >> >> SDP with no m line should be fine but is there some media >> >> description defined for this purpose? >> >> >> >> Thanks, >> >> ~Vikram >> >> _______________________________________________ >> >> 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 >> > >> >_______________________________________________ >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
