Re: [aqm] Alia Atlas' Yes on draft-ietf-aqm-fq-implementation-03: (with COMMENT)

[Alia Atlas <[e-mail]>]

Fred,

What I am saying is that I have worked with and verified implementations of
Weighted Fair Queuing - and it is not Calendar Queues - certainly not as
this
draft describes it.  Can you please provide a reference to what Weighted
Fair
Queues means - if it isn't Weighted Fair Queuing, or fix the draft's
description
(which could be merely mentioning Weighted Fair Queuing as a different
work-conserving approach).

I realize that this is tangential to the point of the draft (or it would
have been
a Discuss), but I still would strongly prefer accuracy.

Regards,
Alia

On Thu, Oct 22, 2015 at 11:57 AM, Fred Baker (fred) <[e-mail]> wrote:

>
> > On Oct 21, 2015, at 6:22 PM, Alia Atlas <[e-mail]> wrote:
> >
> > Alia Atlas has entered the following ballot position for
> > draft-ietf-aqm-fq-implementation-03: Yes
> >
> > When responding, please keep the subject line intact and reply to all
> > email addresses included in the To and CC lines. (Feel free to cut this
> > introductory paragraph, however.)
> >
> >
> > Please refer to
> https://www.ietf.org/iesg/statement/discuss-criteria.html
> > for more information about IESG DISCUSS and COMMENT positions.
> >
> >
> > The document, along with other ballot positions, can be found here:
> > https://datatracker.ietf.org/doc/draft-ietf-aqm-fq-implementation/
> >
> >
> >
> > ----------------------------------------------------------------------
> > COMMENT:
> > ----------------------------------------------------------------------
> >
> > Thank you for a clear and well-written draft.
> >
> > I would like to understand the reference of "Weighted Fair Queues" and
> have that clarified in the draft. It's a technical concern, but I have
> confidence that the authors and ADs will address it.
> >
> > 1) Sec 2.2.3 refers to "Weighted Fair Queues" as well as "Calendar
> Queues". Perhaps it is due to a lack in my recent background - but what's
> described is nothing like Weighted Fair Queuing (
> https://en.wikipedia.org/wiki/Weighted_fair_queueing). Do you have a
> reference for "Weighted Fair Queues" or something else in mind??
>
> Thanks for your question. The original intent of this draft was simply to
> support a discussion, which I expected might be closed without needing to
> publish an RFC. The working group decided that it wanted to adopt and
> publish the note, which is fine as well.
>
> I think what you're looking at is the difference between theory and
> practice. As you know, in theory, they are the same thing, and in practice
> there can be important differences. If you read early papers, such as
> McKenny's SFQ or Lixia Zhang's Virtual Clock, they talk a lot about
> WRR-based implementations; calendar queues came later. But no real
> implementation I am aware of (I have written two and am aware of several
> others) attempts to implement GPS as the GPS paper describes it - nor does
> the GPS paper expect them to. That's why that section in the draft is
> titled "Approximations to GPS" - any implementation is necessarily an
> approximation, and GPS describes the theoretical best case they are trying
> to approximate.
>