Compatibility

De jure standards:

ITU G 723.1/G.729 and H.323

De facto standards:

Adobe Pacifica - SIP based high quality VoIP for Flash

Session Initiation Protocol (SIP) RFC 2543 is much simpler than H.323

An emerging area is Web Real Time Communication (WebRTC) - see for example http://sipml5.org/ Links to an external site. for a HTML5 SIP client uses a WebRTC to SIP proxy (http://webrtc2sip.org/).

Slide Notes

[RFC 2543] M. Handley, H. Schulzrinne, E. Schooler, and J. Rosenberg, “SIP: Session Initiation Protocol”, IETF, Network Working Group, RFC 2543, March 1999, Obsoleted by RFC 3261, RFC 3262, RFC 3263, RFC 3264, RFC 3265, http://datatracker.ietf.org/doc/rfc2543/ Links to an external site.<

Transcript

[slide40] Well, there are a bunch of different de jure standards, those particularly for CODECs by the ITU. But there are also a bunch of de facto standards that various companies have put forward. There's the session initiation protocol, which the IETF has heavily driven. And it's pretty widely used. One of the reasons why we'll look at it is much simpler than H.323. H.323 turns out to be a complex protocol and it's only a binary protocol. Whereas SIP has a nice advantage that it's very readable. But a really interesting emerging technology, and someone is asking about projects, is web real-time communication, called WebRTC. And why is this so interesting? Well, it turns out that WebRTC today is built into most web browsers. So that means that you can set up a multimedia session between your web browser and someone else's. And it's built in. An underlying protocol it's actually using to carry the media is RTP. In particular, it's actually using secure RTP. But what is it missing? It's missing the SIP component because there's nothing pre-built into the system that lets you set up the sessions between the other users. Oops, we forgot that part. But the problem was they couldn't agree on that part. But they could agree that, yes, we're going to carry the media by RTP, so they implemented that. They said, let everyone roll their own front end on it. But we'll make sure that we have a common method of delivering the media. So this is, I think, a very, very, very interesting area today. Because what's the standard interface that everyone has to almost everything? A web browser. So if you have an HTML5 web browser, boom, off you go.