Peer-to-Peer video from iOS to Android?

I'm start to develop/prototype a Peer-to-Peer video chat application for iOS and Android. I'm trying to create a similar experience to FaceTime or Tango -- ie good quality video, works across the internet/3G (not just on the same LAN).

I'm just getting started in the research phase. I've done a bunch of Googling, but haven't found much (since this is a new area for me, I'm probably looking in the wrong places).

Can you suggest any pit falls that I should expect to run into? What protocols should I use (from the reading I've done it looks like people use SIP or XMPP, are these the best options?). Am I going to have a problem doing cross platform communication like this?

Any other resources I should explore. Most of my experience is in developing web applications and b开发者_JAVA百科ackend server-side stuff. So this is a new endevour for me, but I'm looking forward to the mind stretch.

Thanks!

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When you are looking into Peer-to-Peer, you have to clarify what generation of P2P you want to integrate. An interesting overview is given in the following paper http://www.mediateam.oulu.fi/publications/pdf/570.pdf

According to your information you also want to support mobile internet connection. So in my opinion XMPP would be the right place to start. As you might already know, Google uses XMPP in their own Google Talk application and has provided some nice extensions that you can use on your own: https://developers.google.com/talk/talk_developers_home