Audio/Video Transport (avt)

Audio/Video Transport (avt)
---------------------------

Charter
Last Modified: 2007-01-11

Current Status: Active Working Group

Chair(s):
Colin Perkins <[email protected]>
Tom Taylor <[email protected]>
Roni Even <[email protected]>

Real-time Applications and Infrastructure Area Director(s):
Jon Peterson <[email protected]>
Cullen Jennings <[email protected]>

Real-time Applications and Infrastructure Area Advisor:
Cullen Jennings <[email protected]>

Mailing Lists:
General Discussion:[email protected]
To Subscribe: https://www1.ietf.org/mailman//listinfo/avt
Archive: http://www.ietf.org/mail-archive/web/avt/index.html

Description of Working Group:

The Audio/Video Transport Working Group was formed to specify a
protocol for real-time transmission of audio and video over unicast
and multicast UDP/IP. This is the Real-time Transport Protocol, RTP,
together with its associated profiles and payload formats. The current
aims of the working group are:

- to review and revise existing payload formats to advance those which
are useful to Draft Standard, and to declare others as
Historic. Milestones will be established as a champion for each
payload format is identified.

- to develop payload formats for new media codecs, and to document
best-current practices in payload format design. The group continues
to be precluded from work on codecs themselves because of overlap with
the other standards bodies, and because the IETF does not have the
ability to effectively review new codecs. An exception was made for
the freeware iLBC codec on a highly experimental basis, but acceptance
of new codec work is unexpected and subject to rechartering.

- to complete the forward error correction work to update RFC 2733 in
the form of the ULP payload format

- to extend RTP to work with Source-Specific Multicast sessions with
unicast feedback

- to provide a framing mechanism for RTP over TCP and TLS

- in collaboration with the MPLS and ROHC WGs, to develop a solution
for
header compression of RTP across MPLS networks that avoid
decompression and compression at each MPLS node.

- to develop a new RTP profile for the combination of the SRTP profile
and the Extended RTP Profile for RTCP-based Feedback (RTP/SAVPF)

- to maintain and enhance the SRTP Profile, with review and input from
the Security Area

- to develop a new RTP profile for usage of TFRC (RFC 3448) with RTP
over UDP to allow application developers to gain experience with TCP
friendly congestion control.

- to develop a MIB for RTCP XR (RFC 3611).

- to update the RTP MIB, including aligning it with RFC 3550.

- to clarify how RTP is used for media in conferencing with centralized
nodes performing relay, translation or mixing of media.

- to develop the mechanisms needed for efficient control of media and
its encoding process in RTP based conferencing, both over multicast
and transport containing relays, translators and mixers. An example of
such a mechanism is a method to request a full intra coded frame of
video. This would be used to allow joining participants to receive
video immediately after joining instead of waiting for the next intra
coded frame. It also allows mixers to perform switching between media
sources without the need to re-encode the media.

- to develop a solution for carrying media meta data, specifically
SMPTE timestamps, to enhance the media stream. Such transport may be
done in either RTP or RTCP depending on which is most suitable. The WG
may consider if a generalized mechanism should be developed to enable
future types of meta data to be easier to include.

- to develop two new metric blocks for the RTCP XR (RFC 3611) framework
to provide information on the media quality experienced by the
receiver of RTP flows. One metrics block is for high resolution
measurements of audio and speech quality. A second one for providing
information on the quality of video. The timescale to complete this
second block and the included metrics are highly dependable on the
development of standardized subjective metrics for video quality. The
WG will consider what metrics that are available and if they should be
included or not. The metrics blocks shall not duplicate signaling
information anyway necessary for the establishment of the session.

The longer term goals of the working group are to advance the SRTP
Profile, the Extended RTP Profile for RTCP-based Feedback, the
Compressed RTP framework, and the RTP MIB to Draft Standard.

The group has no plans to develop new RTP profiles beyond those listed
above, but will consider rechartering to produce profile level
extensions if appropriate.

Goals and Milestones:

Done Review DCCP including prototypes and API; feedback to DCCP WG

Done Initial draft requirements for ECRTP over MPLS; discuss with
MPLS WG

Done Submit iLBC payload format for Proposed Standard

Done Submit iLBC codec specification for Experimental

Done Advance RTP specification and A/V profile to Full Standard

Done Submit RTP/SAVPF profile for Proposed Standard

Done Finished investigation of advanced FEC codes for RTP, update
plan

Done Submit ULP Payload Format for Proposed Standard

Feb 2007 Submit SMTPE Timestamping of Media for Proposed Standard

Feb 2007 Submit Codec Control Messages for Proposed Standard

Mar 2007 Submit SRTP for Draft Standard

Mar 2007 Submit Multiplexing of RTCP and RTP on the same port for
Proposed Standard

Mar 2007 Submit RTCP XR Video Metrics block for Proposed Standard

Apr 2007 Submit RTCP/SSM draft for Proposed Standard

Jul 2007 Submit update of RTP MIB for Proposed or Draft Standard

Aug 2007 Submit RTCP XR MIB for Proposed Standard

Aug 2007 Submit RTCP XR High Resolution Audio Metrics for Proposed
Standard

Sep 2007 Submit RTP/AVPF for Draft Standard

Internet-Drafts:

Posted Revised I-D Title <Filename>
------ ------- --------------------------------------------
Nov 2000 Jan 2007 <draft-ietf-avt-ulp-21.txt>
RTP Payload Format for Generic Forward Error Correction

Feb 2002 Oct 2006 <draft-ietf-avt-rtcpssm-12.txt>
RTCP Extensions for Single-Source Multicast Sessions with
Unicast Feedback

May 2002 Nov 2006 <draft-ietf-avt-rtp-jpeg2000-12.txt>
RTP Payload Format for JPEG 2000 Video Streams

Oct 2003 Oct 2006 <draft-ietf-avt-profile-savpf-09.txt>
Extended Secure RTP Profile for RTCP-based Feedback (RTP/SAVPF)

Jun 2004 Sep 2006 <draft-ietf-avt-tfrc-profile-06.txt>
RTP Profile for TCP Friendly Rate Control

Aug 2004 Dec 2006 <draft-ietf-avt-rtp-atrac-family-07.txt>
RTP Payload Format for ATRAC Family

Oct 2004 Sep 2006 <draft-ietf-avt-rtp-amr-bis-06.txt>
RTP Payload Format and File Storage Format for the Adaptive
Multi-Rate (AMR) and Adaptive Multi-Rate Wideband (AMR-WB)
Audio Codecs

Feb 2005 Jan 2007 <draft-ietf-avt-rfc2833biscas-03.txt>
Definition of Events For Channel-Oriented Telephony Signalling

Jul 2005 Oct 2006 <draft-ietf-avt-rfc3555bis-05.txt>
Media Type Registration of RTP Payload Formats

Aug 2005 Feb 2007 <draft-ietf-avt-hc-over-mpls-protocol-08.txt>
Protocol Extensions for Header Compression over MPLS

Aug 2005 Feb 2007 <draft-ietf-avt-smpte-rtp-10.txt>
Associating Time-codes with RTP streams

Aug 2005 Mar 2007 <draft-ietf-avt-rtp-hdrext-12.txt>
A general mechanism for RTP Header Extensions

Aug 2005 Jan 2007 <draft-ietf-avt-rfc3047-bis-03.txt>
RTP Payload Format for ITU-T Recommendation G.722.1

Mar 2006 Oct 2006 <draft-ietf-avt-rfc3555bis-part2-02.txt>
Media Type Registration of Payload Formats in the RTP Profile
for Audio and Video Conferences

May 2006 Dec 2006 <draft-ietf-avt-rtp-howto-01.txt>
How to Write an RTP Payload Format

Aug 2006 Feb 2007 <draft-ietf-avt-rtp-toffset-05.txt>
Transmission Time offsets in RTP streams

Aug 2006 Feb 2007 <draft-ietf-avt-topologies-04.txt>
RTP Topologies

Aug 2006 Dec 2006 <draft-ietf-avt-avpf-ccm-03.txt>
Codec Control Messages in the RTP Audio-Visual Profile with
Feedback (AVPF)

Oct 2006 Dec 2006 <draft-ietf-avt-rtp-and-rtcp-mux-03.txt>
Multiplexing RTP Data and Control Packets on a Single Port

Dec 2006 Dec 2006 <draft-ietf-avt-rtcpxr-video-00.txt>
RTCP XR - IP Video Metrics Report Blocks

Dec 2006 Dec 2006 <draft-ietf-avt-rtp-svc-00.txt>
RTP Payload Format for SVC Video

Jan 2007 Mar 2007 <draft-ietf-avt-rfc4695-bis-01.txt>
RTP Payload Format for MIDI

Jan 2007 Jan 2007 <draft-ietf-avt-rtp-evrc-wb-00.txt>
RTP payload format for EVRC-WB codec and MIME updates for
EVRC-B codec

Feb 2007 Feb 2007 <draft-ietf-avt-rtcphr-00.txt>
RTCP HR - High Resolution VoIP Metrics Report Blocks

Request For Comments:

RFC Stat Published Title
------- -- ----------- ------------------------------------
RFC1889 PS Jan 1996 RTP: A Transport Protocol for Real-Time Applications

RFC1890 PS Jan 1996 RTP Profile for Audio and Video Conferences with Minimal
Control

RFC2035 PS Oct 1996 RTP Payload Format for JPEG-compressed Video

RFC2032 PS Oct 1996 RTP payload format for H.261 video streams

RFC2038 PS Oct 1996 RTP Payload Format for MPEG1/MPEG2 Video

RFC2029 PS Oct 1996 RTP Payload Format of Sun's CellB Video Encoding

RFC2190 PS Sep 1997 RTP Payload Format for H.263 Video Streams

RFC2198 PS Sep 1997 RTP Payload for Redundant Audio Data

RFC2250 PS Jan 1998 RTP Payload Format for MPEG1/MPEG2 Video

RFC2343 E May 1998 RTP Payload Format for Bundled MPEG

RFC2354 I Jun 1998 Options for Repair of Streaming Media

RFC2429 PS Oct 1998 RTP Payload Format for the 1998 Version of ITU-T Rec.
H.263 Video (H.263+)

RFC2431 PS Oct 1998 RTP Payload Format for BT.656 Video Encoding

RFC2435 PS Oct 1998 RTP Payload Format for JPEG-compressed Video

RFC2508 PS Feb 1999 Compressing IP/UDP/RTP Headers for Low-Speed Serial
Links

RFC2733 PS Dec 1999 An RTP Payload Format for Generic Forward Error
Correction

RFC2736BCP Dec 1999 Guidelines for Writers of RTP Payload Format
Specifications

RFC2762 E Feb 2000 Sampling of the Group Membership in RTP

RFC2793 PS Jun 2000 RTP Payload for Text Conversation

RFC2833 PS Jun 2000 RTP Payload for DTMF Digits, Telephony Tones and
Telephony Signals

RFC2862 PS Jul 2000 RTP Payload Format for Real-Time Pointers

RFC2959 PS Oct 2000 Real-Time Transport Protocol Management Information Base

RFC3009 PS Dec 2000 Registration of parityfec MIME types

RFC3016 PS Dec 2000 RTP payload format for MPEG-4 Audio/Visual streams

RFC3047 PS Feb 2001 RTP Payload Format for ITU-T Recommendation G.722.1

RFC3119 PS Jun 2001 A More Loss-Tolerant RTP Payload Format for MP3 Audio

RFC3158 I Aug 2001 RTP Testing Strategies

RFC3189 PS Jan 2002 RTP Payload Format for DV Format Video

RFC3190 PS Jan 2002 RTP Payload Format for 12-bit DAT, 20- and 24-bit Linear
Sampled Audio

RFC3267 PS Jul 2002 RTP payload format and file storage format for the
Adoptive Multi-Rate (AMR) and Adaptive Multi-Rate
Wideband (AMR-WB) audio codecs

RFC3389 PS Oct 2002 RTP Payload for Comfort Noise

RFC3497 PS Mar 2003 RTP Payload Format for Society of Motion Picture and
Television Engineers (SMPTE) 292M Video

RFC3558 PS Jul 2003 RTP Payload Format for Enhanced Variable Rate Codecs
(EVRC) and Selectable Mode Vocoders SMV

RFC3557 PS Jul 2003 RTP Payload Format for European Telecommunications
Standards Institute (ETSI) European Standard ES 201 108
Distributed Speech Recognition Encoding

RFC3556 PS Jul 2003 Session Description Protocol (SDP) Bandwidth Modifiers
for RTP Control Protocol (RTCP) Bandwidth

RFC3555 PS Jul 2003 MIME Type Registration of RTP Payload Formats

RFC3551 DS Jul 2003 RTP Profile for Audio and Video Conferences with Minimal
Control

RFC3550 DS Jul 2003 RTP: A Transport Protocol for Real-Time Applications

RFC3545 PS Jul 2003 Enhanced Compressed RTP (CRTP) for links with High
Delay,Packet Loss and Reordering

RFC3611Standard Nov 2003 RTP Control Protocol Extended Reports (RTCP XR)

RFC3640Standard Dec 2003 RTP Payload Format for Transport of MPEG-4 Elementary
Streams

RFC3711Standard Mar 2004 The Secure Real-time Transport Protocol

RFC3951 E Dec 2004 Internet Low Bit Rate Codec

RFC3952 E Dec 2004 RTP Payload Format for iLBC Speech

RFC3984Standard Feb 2005 RTP payload Format for H.264 Video

RFC4040Standard Apr 2005 RTP payload format for a 64 kbit/s transparent call

RFC4060Standard May 2005 RTP Payload Formats for European Telecommunications
Standardsv Institute (ETSI) European Standard ES 202
050, ES 202 211, and ES 202 212 Distributed Speech
Recognition Encoding

RFC4102Standard Jun 2005 Registration of the text/red MIME Sub-Type

RFC4103Standard Jun 2005 RTP Payload for Text Conversation

RFC4175Standard Sep 2005 RTP Payload Format for Uncompressed Video

RFC4184Standard Oct 2005 RTP Payload Format for AC-3 Audio

RFC4247 I Nov 2005 Requirements for Header Compression over MPLS

RFC4170BCP Nov 2005 Tunneling Multiplexed Compressed RTP (TCRTP)

RFC4298Standard Dec 2005 RTP Payload Format for BroadVoice Speech Codecs

RFC4351 H Jan 2006 Real-Time Transport Protocol (RTP) Payload for Text
Conversation Interleaved in an Audio Stream

RFC4348Standard Jan 2006 Real-Time Transport Protocol (RTP) Payload Format for
the Variable-Rate Multimode Wideband (VMR-WB) Audio
Codec

RFC4352Standard Jan 2006 RTP Payload Format for the Extended Adaptive Multi-Rate
Wideband (AMR-WB+) Audio Codec

RFC4396Standard Feb 2006 RTP Payload Format for 3rd Generation Partnership
Project (3GPP) Timed Text

RFC4425 PS Feb 2006 RTP Payload Format for Video Codec 1 (VC-1)

RFC4424 PS Feb 2006 Real-Time Transport Protocol (RTP) Payload Format for
the Variable-Rate Multimode Wideband (VMR-WB) Extension
Audio Codec

RFC4421Standard Feb 2006 RTP Payload Format for Uncompressed Video: Additional
Colour Sampling Modes

RFC4573 PS Jul 2006 MIME Type Registration for RTP Payload Format for H.224

RFC4585 PS Jul 2006 Extended RTP Profile for Real-time Transport Control
Protocol (RTCP)-Based Feedback (RTP/AVPF)

RFC4571 PS Jul 2006 Framing Real-time Transport Protocol (RTP) and RTP
Control Protocol (RTCP) Packets over Connection-Oriented
Transport

RFC4588 PS Jul 2006 RTP Retransmission Payload Format

RFC4598 PS Jul 2006 Real-time Transport Protocol (RTP) Payload Format for
Enhanced AC-3 (E-AC-3) Audio

RFC4587 PS Aug 2006 RTP Payload Format for H.261 Video Streams

RFC4749 PS Oct 2006 RTP Payload Format for the G.729.1 Audio Codec

RFC4696 I Nov 2006 An Implementation Guide for RTP MIDI

RFC4695 PS Nov 2006 RTP Payload Format for MIDI

RFC4734 PS Dec 2006 Definition of Events For Modem, FAX, and Text Telephony
Signals

RFC4733 PS Dec 2006 RTP Payload for DTMF Digits, Telephony Tones and
Telephony Signals

RFC4788 PS Jan 2007 Enhancements to RTP Payload Formats for EVRC Family
Codecs

RFC4629 PS Jan 2007 RTP Payload Format for ITU-T Rec. H.263 Video

RFC4628 I Feb 2007 RTP Payload Format for H.263 using RFC2190 to Historic
status