Preliminary WG Review: RMT WG - Minor Re-Charter

[iesg-secretary@ietf.org]

Reliable Multicast Transport (rmt) Working Group
-------------------------------------------------

Current Status: Active Working Group

 Chairs:
 Roger Kermode <roger.kermode@motorola.com>
 Lorenzo Vicisano <lorenzo@cisco.com>

 Area Director: Allison Mankin <mankin@psg.com>



 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.

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 Drafts for Congestion Control

Done 		Complete most building-block drafts WG Last-Call and submit 
		for publication as Experimental RFC

Done 		Complete building blocks and protocol instantiations for
		ALC and submit for publication as Experimental RFC

MAY 03 	Submit WEBRC (congestion control building block) for
		publication as Experimental

MAY 03 	WG Decision on whether to pursue the router-assist 
		building block work. These milestones may have to be 
		modified accordingly.

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.