Reliable Multicast Transport (rmt)

This Working Group did not meet


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

       http://rmt.motlabs.com -- Additional RMT Web Page
NOTE: This charter is a snapshot of the 59th IETF Meeting in Seoul, Korea. It may now be out-of-date.

Last Modified: 2004-02-02

Chair(s):
Roger Kermode <Roger.Kermode@motorola.com>
Lorenzo Vicisano <lorenzo@cisco.com>
Transport Area Director(s):
Allison Mankin <mankin@psg.com>
Jon Peterson <jon.peterson@neustar.biz>
Transport Area Advisor:
Allison Mankin <mankin@psg.com>
Mailing Lists:
General Discussion: rmt@ietf.org
To Subscribe: rmt-request@ietf.org
In Body: subscribe
Archive: www.ietf.org/mail-archive/working-groups/rmt/current/maillist.html
Description of Working Group:
The purpose of this WG is to standardize reliable multicast transport.

Initial efforts have focused solely on the standardization of the one-to-many transport of large amounts of data. Due to the large number of applications that fall into this category, and the sometimes orthogonal requirements these applications exhibit, it is believed that a "one size fits all" protocol will be unable to meet the requirements of all applications. In recognition of this observation, this working group will standardize two protocol instantiations, initially as Experimental protocols, and then as warranted, in the standards track, from the following families:

1) A NACK-based protocol. 2) An "Asynchronous Layered Coding protocol that uses Forward Error Correction.

The WG will carry out protocol standardization in general by composing a a set of RFCs that specify

- building blocks: A set of easily-separable coarse-grained modular components that are common to multiple protocols along with abstract APIs that define a building block's access methods and their arguments.

- protocol instantiations: Specifications that define the necessary gluing logic and minimal additional functionality required to realize a working protocol from one or more building blocks. These specifications will also include an abstract API that defines the interface between the protocol implementation and an application.

The WG has previously completed work on three documents to assist in the standardization process. RFC2887 describes the design-space in which the one-to-many transport protocols will be developed. RFC3048 explains the concepts of building-blocks and protocol instantiations. RFC3269 provides guidelines to authors of drafts that specify building-blocks and protocol instantiations.

The WG will generate and submit for standardization drafts of the following building-blocks for use in the construction of the two protocols: congestion control, negative acknowledgments, forward error correction, and to address the RFC 2357 security requirements.

Generic mechanisms for router assist are also considered for an additional building block. Initial work on the framework for router-assist has already been performed, the WG will evaluate whether to complete this task basing on available resource and interest.

The WG will also standardize and generate RFCs for the following two protocol instantiations: A NACK-based protocol, and an Asynchronous Layered Coding (ALC) protocol that uses Forward Error Correction. RFC 3450 is the Experimental RFC of the ALC protocol instantiation.

If new requirements are identified that cannot be satisfied with the building-blocks and protocol instantiations described above, the Area Directors in consultation with the IESG may add additional building-blocks and protocol instantiations to the working group deliverables.

This working group will work closely with the Internet Research Task Force (IRTF) groups on Reliable Multicast (RMRG) and Secure Multicast (SMUG), especially for meeting the congestion control and security requirements mandated by RFC 2357. This working group may work with the Area Directors to recharter to standardize reliable multicast for additional scenarios beyond the one-to-many transport of bulk data once they are sufficiently well understood.

Goals and Milestones:
Done  Submit design-space, building-blocks, and guidelines drafts for publication as Informational RFCs
Done  Initial Drafts for the following building blocks: negative acknowledgments, forward error correction, a generic signaling mechanism for router assist, and transport protection
Done  Submit Initial Drafts for the two protocol instantiations.
Done  Submit Initial Draft for Congestion Control
Done  Complete building-block drafts WG Last-Call and submit for publication as Proposed Standard
Done  Complete building blocks and protocol instantiations for ALC and submit for publication as Experimental RFC
Done  WG Decision on whether to pursue the router-assist building block work. These milestones may have to be modified accordingly
Done  Submit WEBRC (congestion control building block) for publication as Experimental
Aug 03  Submit remaining congestion control building blocks (TFMCC, PGMCC) for publication as Experimental
Aug 03  Submit NACK building block and protocol instantiation for publication as Experimental
Dec 03  Evaluate when and how the RMT Experimental specifications will be submitted for publication as Proposed Standard, and update this charter accordingly
Internet-Drafts:
  • - draft-ietf-rmt-bb-norm-08.txt
  • - draft-ietf-rmt-pi-norm-09.txt
  • - draft-ietf-rmt-bb-webrc-04.txt
  • - draft-ietf-rmt-bb-fec-supp-compact-01.txt
  • - draft-ietf-rmt-flute-07.txt
  • Request For Comments:
    RFCStatusTitle
    RFC2887 I The Reliable Multicast Design Space for Bulk Data Transfer
    RFC3048 I Reliable Multicast Transport Building Blocks for One-to-Many Bulk-Data Transfer
    RFC3269 I Author Guidelines for RMT Building Blocks and Protocol Instantiation documents
    RFC3450 E Asynchronous Layered Coding protocol instantiation
    RFC3451 E Layered Coding Transport (LCT) Building Block
    RFC3452 E Forward Error Correction Building Block
    RFC3453 I The use of Forward Error Correction in Reliable Multicast

    Current Meeting Report

    None received.

    Slides

    None received.