1. Introduction

When initiating multimedia teleconferences, voice-over-IP calls, streaming video, or other sessions, there is a requirement to convey media details, transport addresses, and other session description metadata to the participants.

SDP (Session Description Protocol) provides a standard representation for such information, irrespective of how that information is transported. SDP is purely a format for session description -- it does not incorporate a transport protocol, and it is intended to use different transport protocols as appropriate, including the Session Announcement Protocol [14], Session Initiation Protocol (SIP) [15], Real Time Streaming Protocol (RTSP) [16], electronic mail using the MIME extensions, and the Hypertext Transport Protocol (HTTP).

SDP is intended to be general purpose so that it can be used in a wide range of network environments and applications. However, it is not intended to support negotiation of session content or media encodings: this is viewed as outside the scope of session description.

This memo obsoletes RFC 2327 [6] and RFC 3266 [10]. Section 10 outlines the changes introduced in this memo.