The solution really depends on the details of your use case and the acceptable delay it would require. You can go for a P2P mesh topology, or you can just use streaming media servers in the backend ; in that case you will use WebRTC from your web app to the server, then the server route/transcode/optimize the distribution of the stream to the clients.

A few resources: - https://tokbox.com/platform/beta-programs/ - http://www.streamroot.io - https://www.peer5.com - https://webtorrent.io - http://www.dialogic.com/en/landing/webrtc.aspx - https://jitsi.org/Projects/JitsiVideobridgePerformance