Why SIP??

Archived from groups: comp.dcom.voice-over-ip,comp.dcom.videoconf (More info?)

Hi all,

Can Any one point out some advantages of SIP, that why we need SIP in
application like Video Conferencing, which we can't get without it.
Though some of them I think are,

1. To make a consensus between the the user of application/system,
over the characteristic of media to be used in conference.

2. Call making would be transparent, like either caller or callee can
be a Desktop application, IP telephone, PSTN user etc.

3. Maintains state about session being establish for some features
like billing etc.

4. Locating prospective session participants.

Can any body add some more features, or make any comments. Any effort
will be appriciated.

Rajat