---

title: SDP

slug: Glossary/SDP

page-type: glossary-definition

---

{{GlossarySidebar}}

**SDP** (Session Description {{glossary("Protocol")}}) is the standard describing a {{Glossary("P2P","peer-to-peer")}} connection. SDP contains the {{Glossary("codec")}}, source address, and timing information of audio and video.

Here is a typical SDP message:

```plain

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 {{Glossary("RTP")}} and {{Glossary("RTSP")}}. SDP is also a component of {{Glossary("WebRTC")}}, which uses SDP as a way of describing a session.

## See also