Requirements for Advanced Multipath in MPLS Networks

Approval announcement
Draft of message to be sent after approval:

From: The IESG <>
To: IETF-Announce <>
Cc: RFC Editor <>
Subject: Document Action: 'Requirements for Advanced Multipath in MPLS Networks' to Informational RFC (draft-ietf-rtgwg-cl-requirement-16.txt)

The IESG has approved the following document:
- 'Requirements for Advanced Multipath in MPLS Networks'
  (draft-ietf-rtgwg-cl-requirement-16.txt) as Informational RFC

This document is the product of the Routing Area Working Group.

The IESG contact persons are Stewart Bryant and Adrian Farrel.

A URL of this Internet Draft is:

Technical Summary

   There is often a need to provide large aggregates of bandwidth that
   are best provided using parallel links between routers or MPLS LSP.
   In core networks there is often no alternative since the aggregate
   capacities of core networks today far exceed the capacity of a single
   physical link or single packet processing element.

   The presence of parallel links, with each link potentially comprised
   of multiple layers has resulted in additional requirements.  Certain
   services may benefit from being restricted to a subset of the
   component links or a specific component link, where component link
   characteristics, such as latency, differ.  Certain services require
   that an LSP be treated as atomic and avoid reordering.  Other
   services will continue to require only that reordering not occur
   within a microflow as is current practice.

Working Group Summary

Interest in the draft was mild - focus mostly from a small set of participants
and the co-authors.  There were no contentious points.  There was discussion
about the value of DR#6 where the overhead of just signaling the composite link
members may be better than dealing with crankback or poor summarization. 
The work can support both approaches.

After the last WGLC completed, there was concern about the terminology of
composite link not quite matching that used in the ITU.  The draft has been
updated to use the term "Advanced Multipath" instead.  Some additional 
simplifications were also made by the authors' agreement.

During IETF Last Call there was a significant discussion between the 
Routing Directorate reviewer and the Editor which led to further updates
to the text.

Document Quality

The document is well written and has been updated with focus several times.
It has benefited from having Curtis Villamizar being a focused and motivated
editor for this and the related drafts.

There are no existing implementations, as makes sense for a requirements draft.


Document Shepherd: Alia Atlas
Responsible AD:  Stewart Bryant