Chat Protocols and Client to client connection?
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I'm looking for a protocol/API to implement a video chat application. In this app, the clients connect to a server and when two clients start chat, they don't send/receive data to/from server! Actually I want the clients connect to each other straightly. I want this on iPhone and Android.
I've searched, and found XMPP protocol, but I'm not sure it let p2p connection. 
Anyway, is it possible?