Negotiating Media Multiplexing Using the Session Description Protocol (SDP)
MMUSIC Working Group C. Holmberg
Obsoletes: 8843 (if approved) H. Alvestrand
Updates: 3264, 5888, 7941 (if approved) Google
Intended status: Standards Track C. Jennings
Expires: 2 October 2021 Cisco
31 March 2021
Negotiating Media Multiplexing Using the Session Description Protocol
This specification defines a new Session Description Protocol (SDP)
Grouping Framework extension called 'BUNDLE'. The extension can be
used with the SDP offer/answer mechanism to negotiate the usage of a
single transport (5-tuple) for sending and receiving media described
by multiple SDP media descriptions ("m=" sections). Such transport
is referred to as a BUNDLE transport, and the media is referred to as
bundled media. The "m=" sections that use the BUNDLE transport form
a BUNDLE group.
This specification defines a new RTP Control Protocol (RTCP) Source
Description (SDES) item and a new RTP header extension.
This specification updates RFCs 3264, 5888, and 7941.
This specification obsoletes RFC 8843.
Status of This Memo
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This Internet-Draft will expire on 2 October 2021.
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Table of Contents
1.2. BUNDLE Mechanism
1.3. Protocol Extensions
1.4. Changes from RFC 8843
4. Applicability Statement
5. SDP Grouping Framework BUNDLE Extension
6. SDP 'bundle-only' Attribute
7. SDP Offer/Answer Procedures
7.1. Generic SDP Considerations
7.1.1. Connection Data ("c=")
7.1.2. Bandwidth ("b=")
7.1.3. Attributes ("a=")
7.2. Generating the Initial SDP Offer
7.2.1. Suggesting the Offerer-Tagged 'm=' Section
7.2.2. Example: Initial SDP Offer
7.3. Generating the SDP Answer
7.3.1. Answerer Selection of Tagged 'm=' Sections
7.3.2. Moving a Media Description Out of a BUNDLE Group
7.3.3. Rejecting a Media Description in a BUNDLE Group
7.3.4. Example: SDP Answer
7.4. Offerer Processing of the SDP Answer
7.5. Modifying the Session
7.5.1. Adding a Media Description to a BUNDLE Group
7.5.2. Moving a Media Description Out of a BUNDLE Group
7.5.3. Disabling a Media Description in a BUNDLE Group
8. Protocol Identification
8.1. STUN, DTLS, and SRTP
9. RTP Considerations
9.1. Single RTP Session
9.1.1. Payload Type (PT) Value Reuse
9.2. Associating RTP/RTCP Streams with the Correct SDP Media
9.3. RTP/RTCP Multiplexing
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