[aqm] Eric Rescorla's No Objection on draft-ietf-aqm-codel-07: (with COMMENT)

Eric Rescorla <ekr@rtfm.com> Fri, 07 April 2017 23:30 UTC

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From: Eric Rescorla <ekr@rtfm.com>
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Date: Fri, 07 Apr 2017 16:30:46 -0700
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Subject: [aqm] Eric Rescorla's No Objection on draft-ietf-aqm-codel-07: (with COMMENT)
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Eric Rescorla has entered the following ballot position for
draft-ietf-aqm-codel-07: No Objection

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----------------------------------------------------------------------
COMMENT:
----------------------------------------------------------------------

The normative part of this document seems reasonably clear and I
believe I could implement it. Note: I have not attempted to assess the
technical quality of the algorithm described in this protocol.

I found the descriptive part a little hard to follow in places.
Specifically:

- It's a little hard to work out which things are informal terms
  and which are defined terms of art.
  
  "power" is used first on page 4 but it's only clear that
  it's a term of art in S 16. This could be fixed by a
  forward reference and a cite to Kleinrock.

  "target" and "interval" are constants in the algorithm,
  but this wasn't entirely clear to me in S 3.2. You could
  deal with this by stating in S 3 that the algorithm
  takes in two variables (TARGET and INTERVAL). Perhaps
  capitalize them. I see you also use "setpoint" and
  "target" and "target setpoint". I would stick to one
  if you can.

- It seems that the document went through some reordering
  because S 5.1. refers to the pseudo-code as coming later
  in the draft. Perhaps some of the rationale could come
  before the pseudo-code. Specifically, the intuition that
  the dropping happens only when you are able to send
  packets (dequeue) is kind of counter-intuitive.

- Following up on the above point, you must be able to
  drop packets when the queue is entirely full, but S
  4.4 doesn't seem to contemplate this. What is the impact
  of this? You just drop and ignore?

Finally, you seem a bit inconsistent about whether you are
capitalizing 2119 terms (see for instance the use of should
vs. SHOULD in the second graf of S 3.2).