Using BGP to Bind MPLS Labels to Address Prefixes
RFC 8277

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: draft-ietf-mpls-rfc3107bis@ietf.org, db3546@att.com, mpls@ietf.org, mpls-chairs@ietf.org, Loa Andersson <loa@pi.nu>, The IESG <iesg@ietf.org>, rfc-editor@rfc-editor.org, loa@pi.nu
Subject: Protocol Action: 'Using BGP to Bind MPLS Labels to Address Prefixes' to Proposed Standard (draft-ietf-mpls-rfc3107bis-04.txt)

The IESG has approved the following document:
- 'Using BGP to Bind MPLS Labels to Address Prefixes'
  (draft-ietf-mpls-rfc3107bis-04.txt) as Proposed Standard

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

The IESG contact persons are Alvaro Retana, Alia Atlas and Deborah Brungard.

A URL of this Internet Draft is:
https://datatracker.ietf.org/doc/draft-ietf-mpls-rfc3107bis/


Technical Summary

 RFC 3107 specifies encodings and procedures for using BGP to
   indicate that a particular router has bound either a single MPLS
   label or a sequence of MPLS labels to a particular address prefix.
   This is done by sending a BGP UPDATE message whose Network Layer
   Reachability Information field contains both the prefix and the
   MPLS label(s), and whose Next Hop field identifies the node at
   which said prefix is bound to said label(s). Each such UPDATE also
   advertises a path to the specified prefix, via the specified next
   hop.

   Although there are many implementations and deployments of 
   RFC3107, there are a number of issues with [RFC3107] that have 
   impeded interoperability in the past, and may potentially impede
   interoperability in the future.

   This document replaces and obsoletes RFC 3107.  It defines a new
   BGP Capability to be used when binding a sequence of labels to 
   a prefix; by using this Capability, the interoperability problems
   alluded to above can be avoided.

   This document also removes the unimplemented "Advertising Multiple
   Routes to a Destination" feature, while specifying how to use 
   RFC 7911 to provide the same functionality.

   This document also addresses the issue of the how UPDATEs that 
   bind labels to a given prefix interact with UPDATEs that advertise 
   paths to that prefix but do not bind labels to it.  However, for 
   backwards compatibility, it declares most of these interactions 
   to be matters of local policy.

Working Group Summary

 The MPLS working group does solidly support this docment, it 
  address well known interoperability problems. We had a good number
  of people supporting working group adoption and later (in the 
  working last call) supporting publication.

  The document has also been working group last called in IDR and
  bess, the support from these groups are also strong.

  There has been no controversies around this update of RFC 3107.

Document Quality

We know of several implementations of RFC 3107, thus a very good
understanding of the interoperability problems. We also know of 
intents to implement the updated version. An implementation poll
has been started, and as soon as we have new information will 
update this Shepherd Write-up.

Personnel

   Who is the Document Shepherd for this document? Loa Andersson 
   Who is the Responsible Area Director? Deborah Brungard