Internet Engineering Task Force

Audio/Video Transport (avt)

In addition to this official charter maintained by the IETF Secretariat, there is additional information about this working group on the Web at:
RTP FAQ Page

Last Modified: 2010-11-04

Additional information is available at tools.ietf.org/wg/avt

Chair(s):

Real-time Applications and Infrastructure Area Director(s):

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, along with its
associated profiles and payload formats.

RTP itself has been shepherded to Full Standard. Its associated
profiles, extensions, and payload formats are currently at various
levels of stardards maturity. This working group's current work
centers in four areas:

1) Maintenance of the core RTP/RTCP protocols and the AVP, SAVP, AVPF,
and SAVPF profiles

2) Specification and maintenance of payload formats for use with RTP

3) Specification of metric blocks for use with the RTCP Extended Report
(XR) framework

4) Extensions to the core protocols to facilitate joining,
synchronizing, control, and monitoring of RTP multimedia
sessions

In these areas, the group is chartered to focus on the following
tasks. Work supporting those areas, but not reflected in these
tasks must not be accepted by the working group without an explicit
re-chartering. In particular, new items supporting the fourth area
are expected to be reviewed in DISPATCH before being considered new
charter items for this group.

1) Maintenance of the core RTP/SRTP/RTCP protocols
and the AVP, SAVP, AVPF, and SAVPF profiles
- maintain and enhance the SRTP Profile, with review and input
from the Security Area
- specify how to use Explicit Congestion Notification (ECN)
with RTP/RTCP
- continue to investigate the export of summarized RTP/RTCP
information for operations and monitoring purposes

2) Specification and maintenance of payload formats for use with RTP
- provide guidelines for payload format design
- develop payload formats for new media codecs
- review and revise existing payload formats to advance those
which are useful to Draft Standard or Standard, and to
declare others as Historic.

3) Specification of metric blocks for use with the
RTCP Extended Report (XR) framework
- provide a mechanism allowing identification data for
a set of related metric reports to be carried separately
and identified in those reports by reference
- provide report blocks for delay, delay variation, and discard
- provide report blocks for burst/gap discard and loss
- provide report blocks supporting rapid synchronization
of multiple RTP streams
- provide report blocks for jitter buffer metrics
- provide report blocks for loss concealment metrics

4) Extensions to the core protocols to facilitate joining,
synchronizing, control, and monitoring of RTP multimedia
sessions
- develop tools to support rapid acquisition of multimedia streams
- specify necessary extensions to support rapid synchronization of
multiple RTP streams

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
Done		Submit SMTPE Timestamping of Media for Proposed Standard
Done		Submit Codec Control Messages for Proposed Standard
Done		Submit Multiplexing of RTCP and RTP on the same port for Proposed Standard
Done		Submit RTCP/SSM draft for Proposed Standard
Done		Submit draft on Enhancing RTP header extensions for proposed standard
Done		Submit RTP Payload Format for ITU-T Recommendation G.711.1 for Proposed Standard
Done		Submit RTP payload format for mU-law EMbedded Codec for Low-delay IP communication (UEMCLIP) speech codec for Proposed Standard
Done		Submit Transmission Time offsets in RTP streams for Proposed Standard
Done		Submit RTP Payload Format for Adaptive TRansform Acoustic Coding (ATRAC) Family for Proposed Standard
Done		Submit RTP Payload Format for JPEG 2000 Video Streams for Proposed Standard
Done		Submit Payload Format for JPEG 2000 Video: Extensions for Scalability and Main Header Recovery for Proposed Standard
Done		Submit RTP Payload Format for the Speex Codec for Proposed Standard
Done		Submit G.729.1 RTP Payload Format update: DTX support for Proposed Standard
Done		Submit RTP Payload Format for ITU-T Recommendation G.722.1 for Proposed Standard
Done		Submit draft on Mechanisms to keep NAT bindings for RTP flows alive for BCP
Done		Submit The SEED Cipher Algorithm and Its Use with the Secure Real-time Transport Protocol (SRTP) for Proposed Standard
Done		Submit RTP Payload Format for Elementary Streams with MPEG Surround multi-channel audio for Proposed Standard
Done		Submit Support for reduced size RTCP, opportunities and consequences
Done		Submit RTP Payload Format for SPIRIT IP-MR Speech Codec Software for Proposed Standard
Done		Submit Post-Repair Loss RLE Report Block Type for RTCP XR for Proposed Standard
Done		Submit RTP Payload Format for H.264 Video for Proposed Standard
Done		Submit RTP Payload Format for G.719 audio for Proposed Standard
Jan 2010		RTP Payload Format for DRA Audio for Informational
Done		Policy for Registering SRTP Transforms for Proposed Standard
Done		RTP Payload Format for GSM-HR for Proposed Standard
Done		Submit draft explaining why SRTP need not be mandatory for media transport, for Informational
Done		Submit Rapid Synchronization of RTP Flows for Proposed Standard
Done		Submit Forward-shifted RTP Redundancy Payload Support for Proposed Standard
Done		Submit Unicast-Based Rapid Acquisition of Multicast RTP Sessions for Proposed Standard
Done		Submit RTP Payload Format for H.264 RCDO Video for Proposed Standard
Done		Submit RTP Payload Format for SVC Video for Proposed Standard
Mar 2010		Submit EVBR/G.718 payload draft for Proposed Standard
Done		Submit Guidelines for Extending the RTP Control Protocol (RTCP) for Informational
Aug 2010		Submit Guideline for Choosing RTCP CNAME as proposed standard
Aug 2010		Submit Multicast Acquisition Report Block Type for RTCP XR
Aug 2010		RTP Payload Format for MPEG-4 Audio/Visual Streams for Proposed Standard
Done		Submit RTCP port for multicast sessions as proposed standard
Sep 2010		RTP profile for the carriage of SMPTE 336M data for Proposed Standard
Sep 2010		RTP Payload Format for the iSAC codec for Proposed Standard
Sep 2010		RTP Payload Format for the CELT codec for Proposed Standard
Sep 2010		Submit in band keying mechanism for SRTP draft for Proposed Standard
Sep 2010		Submit Port Mapping Between Unicast and Multicast RTP Sessions for Proposed Standard
Sep 2010		RTP Payload Format for Enhanced Variable Rate Narrowband- Wideband Codec (EVRC-NW) for Proposed Standard
Sep 2010		RTP Payload Format for MPEG2-TS preamble for Proposed Standard
Sep 2010		Submit RTP Payload Format for DV (IEC 61834) Video for Proposed Standard
Sep 2010		Submit use of AES-192 and AES-256 in Secure RTP for Proposed Standard
Oct 2010		RTP Payload Format for MVC Video for Proposed Standard
Nov 2010		Submit Explicit Congestion Notification (ECN) for RTP over UDP for Proposed Standard
Nov 2010		Encryption of Header Extensions in the Secure Real-Time Transport Protocol (SRTP) for Proposed Standard
Nov 2010		RTP Payload Format for Bluetooth's SBC audio codec for Proposed Standard
Dec 2010		Submit RTP Payload Format for MIDI for Proposed Standard
Dec 2010		Submit Real-Time Transport Control Protocol (RTCP) in Overlay Multicast for Proposed Standard
Dec 2010		Submit Considerations for RAMS Scenarios for Informational
Feb 2011		Submit Monitoring Architecture for RTP for Informational
Feb 2011		Submit How to Write an RTP Payload Format for Informational
Feb 2011		Using the results of the work for Monitoring Architecture for RTP, submit work proposal (milestones) for monitoring: Measurement Identity, Burst/Gap Discard metric Reporting, Burst/Gap Loss metric Reporting, Concealed Seconds metric Reporting, Delay metric Reporting, Discard metric Reporting, Jitter Buffer Metric Reporting, Loss Concealment metric Reporting, Packet Delay Variation Metric Reporting, QoE Metrics Reporting
Feb 2011		Submit Real-time Transport Control Protocol Extension Report for Run Length Encoding of Discarded Packets

Internet-Drafts:

Request For Comments: