SDP (Session Description Protocol) is the standard describing a peer-to-peer connection. SDP contains the codec, source address, and timing information of audio and video.
Here is a typical SDP message:
v=0 o=alice 2890844526 2890844526 IN IP4 host.anywhere.com s= c=IN IP4 host.anywhere.com t=0 0 m=audio 49170 RTP/AVP 0 a=rtpmap:0 PCMU/8000 m=video 51372 RTP/AVP 31 a=rtpmap:31 H261/90000 m=video 53000 RTP/AVP 32 a=rtpmap:32 MPV/90000
SDP is never used alone, but by protocols like RTP and RTSP. SDP is also a component of WebRTC, which uses SDP as a way of describing a session.
- WebRTC protocols
- Session Description Protocol on Wikipedia