Re: [tcpm] finalizing CUBIC draft (chairs' view)

Yoshifumi Nishida <> Tue, 06 September 2022 06:13 UTC

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From: Yoshifumi Nishida <>
Date: Mon, 05 Sep 2022 23:13:23 -0700
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Subject: Re: [tcpm] finalizing CUBIC draft (chairs' view)
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Hi folks,

We're looking for some feedback on this to finalize the CUBIC draft.
Based on the previous discussions, I am thinking that one way to proceed is
to add some explanations (not a solution!) for the points below in the
If you have some proposed texts on this point or you have different ideas,
please let us know.
If there's no opinion, I might propose some texts for them.

On Fri, Aug 26, 2022 at 12:40 AM Yoshifumi Nishida <>

> Hello everyone,
> Based on the feedback from the last meeting, the chairs have been
> discussing how to finalize the cubic draft.
> The below is our current view on the draft.
> The slide for the CUBIC draft from the last WG meeting listed 4 discussion
> points in the draft.
> >
> In these items, we think that the last two points are already addressed
> now.
> With regard to the remaining two points, our views are the following.
> Point 1: TCP friendly model in the cubic draft
>      We can admit that the model is not valid as the paper describing the
> model uses some simplified presumptions.
>      But, it doesn't not mean the model will pose serious issues on the
> Internet as we haven't seen any evidence yet.
> Point 2: Multicative decrease factor during slow-start phase
>      We think using the current value: 0.7 may cause more packet losses
> in certain cases, but it can work efficiently in other cases.
>      We think this is a part of design choices in CUBIC as we haven't
> seen any tangible evidence that it can cause serious problems.
> We concluded this will require more detailed analysis and evaluations
> which can take a longer time.
> Based on this, we think these points are NOT needed to be addressed in
> the draft while it will be good to add some more explanations for them.
> We saw there were several opinions about documenting these points in the
> draft during the last meeting. If you have some suggestions here, please
> share your opinions.
> Please note that this doesn't mean we'll ignore them. we will try to
> publish a new version of the CUBIC draft if we find some things on them.
> If you have any opinions or comments on the views, please share them with
> us.
> Thanks,
> --
> Yoshi on behalf of tcpm co-chair