Technical Summary
This document is a complete rework of the recommendations to have some form of
active queue management in ideally every queue. While RFC2309 (1998) was mostly
concerned around network stability, and made recommendations which did not
appeal to operators (universal deployment of RED, which has been found to be
particularly hard to configure correctly), this revised document includes the
lessons learned over the past years. Also, the main focus is on reducing network
latency, while still delivering improvements to network stability. It contains
a number of requirements, that a modern AQM mechanism should fulfill, without
endorsing one specific method.
Working Group Summary
There was consensus early on about the aim and technical content of this
document. However, specific wording (e.g. carrying over text from RFC2309, as
this document started off as a 2309bis draft) was objected to.
Also, the question if this document should update or obsolete the earlier BCP
(which was the result of discussions on the end2end mailing list, prior of
formation of the IRTF) has been disussed eagerly.
On the technical grounds to argue for obsoleting the earlier BCP, this document
specifically deprecates RED in favor of one of potentially several more modern
AQM algorithms. Further, a point has been made that since it is not necessary to
read RFC2309 to arrive at a sound understanding of the IETF (WG) consensus
position around AQM, and the deviation is large enough with little overlap, having
this document update 2309 was deemed less appropriate than obsoleting it.
Finally, one active participant has expressed very strong objections to some of
the points summarized above, but later commented that he will accept his
position as "in the rough". So, even though this was voiced at one point in
time, an appeal is not expected.
Document Quality
As a BCP, a number of operators and developers are following up on the updated
recommendations. Newer mechanisms that fulfill the updated requirements have
been developed by multiple parties and are already being deployed by third
parties (e.g. DOCSIS PIE in Cable Modems).
Have a significant number of vendors indicated their plan to implement the
specification?
Yes; As a recommendation, it provides the necessary guidance when mechanisms are
developed. Also, interoperability between AQMs is not as strict as in other
areas, as many variants can be deployed along a path, as long as some over-
arching design principles are adhered to.
Are there any reviewers that merit special mention as having done a thorough
review, e.g., one that resulted in important changes or a conclusion that the
document had no substantive issues?
John Leslie and Bob Briscoe made comments that improved the overall document
text, to align with the technical aim. However, these changes did not modify the
technical content.
Personnel
The Document Shepherd is Richard Scheffenegger.
The Responsible Area Director is Martin Stiemerling.