BTW, when mode is sent in the a line of SDP it is just an indication of the local state. It does in any way mandate a behavior on the remote side which received it. Meaning returning a complimentary mode or inactive when send-only is received or inactive is received etc.
To minimise the media traffic, one end can stop sending if the other side is not listening. Or both ends can stop sending (in-active case) However listening is a local choice, since no rtp packets are received if the other side is not sending it. I am not sure offer/answer mandates the mode to be sent back in Answer when u receive a specific mode in Offer SDP. Kasturi > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On > Behalf Of Paul Kyzivat (pkyzivat) > Sent: Wednesday, June 27, 2007 10:27 AM > To: varun > Cc: [EMAIL PROTECTED] > Subject: Re: [Sip-implementors] Call hold and a = inactive > > > > varun wrote: > > Hi, > > If user B wants to put user A on Hold, it can send a = > sendonly to A > > and expects A to return a = recvonly. > > This way there is a one way audio channel open from B to A. > > What if user A responds with a = inactive..is that valid? > > Yes. > > > Does it mean that media streams are on Hold in both directions? > > It *means* exactly what it says: media is not to be sent in > either direction. It doesn't *mean* any sort of hold. (You > can't really infer the meaning from the signaling. The > meaning is only known locally.) > > For instance it may just be a policy of the other end that it > doesn't want to receive if it can't send. > > SIP has no mechanism that tells the other party that the HOLD > feature has been invoked. The sendonly/recvonly/inactive > mechanism can be *used* when HOLD has been invoked locally, > to optimize the use of the media path. But the same > mechanisms are also used for other purposes. So it is > incorrect to assume the HOLD feature has been invoked when > you receive an offer with sendonly. > > Paul > > > Thanks > > varun > > > > > > > > > ______________________________________________________________________ > > ______________ Take the Internet to Go: Yahoo!Go puts the > Internet in > > your pocket: mail, news, photos & more. > > http://mobile.yahoo.com/go?refer=1GNXIC > > _______________________________________________ > > 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 > _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
