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.
Personnel
Document Shepherd: Alia Atlas
Responsible AD: Stewart Bryant