MPLS Multicast Encapsulations
RFC 5332

Approval announcement
Draft of message to be sent after approval:

From: The IESG <iesg-secretary@ietf.org>
To: IETF-Announce <ietf-announce@ietf.org>
Cc: Internet Architecture Board <iab@iab.org>,
    RFC Editor <rfc-editor@rfc-editor.org>, 
    mpls mailing list <mpls@lists.ietf.org>, 
    mpls chair <mpls-chairs@tools.ietf.org>
Subject: Protocol Action: 'MPLS Multicast Encapsulations' to 
         Proposed Standard 

The IESG has approved the following document:

- 'MPLS Multicast Encapsulations '
   <draft-ietf-mpls-multicast-encaps-11.txt> as a Proposed Standard

This document is the product of the Multiprotocol Label Switching Working 
Group. 

The IESG contact persons are Ross Callon and David Ward.

A URL of this Internet-Draft is:
http://www.ietf.org/internet-drafts/draft-ietf-mpls-multicast-encaps-11.txt

Technical Summary

   RFC 3032 established two data link layer codepoints for MPLS, used to
   distinguish whether the data link layer frame is carrying an MPLS
   unicast or an MPLS multicast packet.  However, this usage was never
   deployed.  This specification updates RFC 3032 by redefining the
   meaning of these two codepoints.  Both codepoints can now be used to
   carry multicast packets.  The second codepoint (formerly the
   "multicast codepoint") is now to be used only on multiaccess media,
   and it is to mean "the top label of the following label stack is an
   upstream-assigned label".

   RFC 3032 does not specify the destination address to be placed in the
   "MAC DA" field of an ethernet frame which carries an MPLS multicast
   packet.  This document provides that specification.

   This document updates RFC 3032 and RFC 4023.

Working Group Summary

   No controversy reported (see PROTO writeup by Loa Andersson).
   This document, along with one other (draft-ietf-mpls-upstream-
   label) are the forerunners on a set of multicast documents that
   are being worked on and have been widely discussed in the working 
   group and will be submitted to the IESG once these two documents
   are approved. 

Document Quality

   The document has been well reviewed, and represents clear consensus
   in the WG. It is also the basis of related ongoing work. 
   Implementation of draft-ietf-mpls-multicast-encaps is quite
   straightforward.  However, in and of itself it is not useful.
   Rather protocol specifications that will make use of this 
   encapsulation are currently being progressed in the MPLS WG.  
   The reason for pushing this document forward at this time is
   because:

    o It forms a clear means of updating RFC 3032

    o Ensures that protocols needing such an encapsulation will be
      done consistently

Personnel

   Loa Andersson is the document shepherd, however both WG chairs 
   (Loa and George) have reportedly reviewed the document. Ross Callon 
   is the responsible AD. Ross will inquire regarding choice of IANA
   expert.