Subject: Re: [rmcat] Please review draft-ietf-rmcat-eval-criteria-01

From: Varun Singh <[email-masked]>
Date: Thu, 12 Jun 2014 14:28:24 +0300

Hi all,

There was one one open issue that needs to be discussed and it is
related to fairness :)

This has been discussed at length in the design group meetings and
also at the IETF meetings, but I am not sure if the text in the open
issue had working group agreement.

The summary of the discussion so far is:
- The eval-criteria needs to define a guideline that helps in
evaluating an RMCAT proposal
- The individual test case should define its expected fairness
criteria, and it may vary between scenarios.

NEW TEXT to replace the open issue:

 Fairness or Unfairness: Experiments testing the performance of an
   RMCAT proposal against any cross-traffic must define its expected
   criteria for fairness.

   The "unfairness" test guideline to assist in defining such a
criteria (measured at 1s intervals) is:
   1.  Does not trigger the circuit breaker.
   2.  When the competing streams with identical RMCAT streams having
similar RTTs,
   no stream achieves over 3 times the min RMCAT stream or less than
1/3 times the
   throughput of the max RMCAT stream.
   3.  When competing with identical RMCAT streams having similar RTTs,
   no RTT measurements for an RMCAT stream is over 3 times delay compared to RTT
   measurements performed before starting the RMCAT flow.

Next step:
Is the guideline helpful and should be in the draft?, or
suggestion, and counter proposals are welcome.

Cheers,
Varun

On Mon, Mar 31, 2014 at 5:02 PM, Mirja Kühlewind
<[email-masked]> wrote:
> Hi group,
>
> draft-ietf-rmcat-eval-criteria-01 was updated after the last meeting
> addressing all comments from the meeting. We would really need people to
> review this document now! Please do so!
>
> https://datatracker.ietf.org/doc/draft-ietf-rmcat-eval-criteria/
>
> Mirja
>
>

-- 
http://www.netlab.tkk.fi/~varun/

---

From: Michael Welzl <[email-masked]>
Date: Fri, 13 Jun 2014 15:07:55 +0200

Hi,

>   throughput of the max RMCAT stream.

In principle, what this new text up to here is trying to say (if I interpret it correctly) sounds good to me.
However, the English is pretty broken, please fix.

>   measurements performed before starting the RMCAT flow.

Huh? "Compared to measurements performed before starting the RMCAT flow" => which one? All, including the background flows, or only the foreground flow? The foreground flow must not make the RTT grow by a factor of 3, is that it? I think that's not a fairness criterion, it's a delay-minimizing criterion, and a weird one too. I wonder if this could just be removed.

Cheers,
Michael