RFC 3407 (rfc3407) - Page 1 of 10
Session Description Protocol (SDP) Simple Capability Declaration
Alternative Format: Original Text Document
Network Working Group F. Andreasen Request for Comments: 3407 Cisco Systems Category: Standards Track October 2002 Session Description Protocol (SDP) Simple Capability Declaration Status of this Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited. Copyright Notice Copyright (C) The Internet Society (2002). All Rights Reserved. Abstract This document defines a set of Session Description Protocol (SDP) attributes that enables SDP to provide a minimal and backwards compatible capability declaration mechanism. Such capability declarations can be used as input to a subsequent session negotiation, which is done by means outside the scope of this document. This provides a simple and limited solution to the general capability negotiation problem being addressed by the next generation of SDP, also known as SDPng. 1. Conventions Used in this Document The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC-2119 [2]. 2. Introduction The Session Description Protocol (SDP) [3] describes multimedia sessions for the purposes of session announcement, session invitation, and other forms of multimedia session initiation. SDP was not intended to provide capability negotiation. However, as the need for this has become increasingly important, work has begun on a "next generation SDP" (SDPng) [4,5] that supports both session description and capability negotiation. SDPng is not anticipated to be backwards compatible with SDP and work on SDPng is currently in the early stages. However, several other protocols, e.g. SIP [6] and Media Gateway Control Protocol (MGCP) [7], use SDP and are likely to Andreasen Standards Track
