What is SDP – Session Description Protocol?

SDP, short for Session Description Protocol, is a format for describing streaming media initialization parameters. It has been published by the IETF as RFC 4566. Streaming media is content that is viewed or heard while it is being delivered. SDP does not deliver the media by itself, rather it negotiates the end points of the media format, its type and all related properties. SDP is designed to be extensible in order to support new media types and formats. SDP has found uses in conjunction with RTP and SIP despite it’s initial beginning as a component of the Session Announcement Protocol (SAP).

Further Reading

RFC 4566
What is SIP?