Re: [tcpm] TCP tuning

John Heffner <johnwheffner@gmail.com> Wed, 03 February 2010 20:31 UTC

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Date: Wed, 03 Feb 2010 15:32:29 -0500
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From: John Heffner <johnwheffner@gmail.com>
To: "tcpm@ietf.org WG" <tcpm@ietf.org>
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Subject: Re: [tcpm] TCP tuning
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I would like to see tcpm take on the initial window issue, though as
Joe notes we probably do not yet know enough to formally take this on
as a charter item.  (Or, would this be a tsvwg item due to possible
wider impact?)

A couple thoughts:
- A large initial window should probably only be used by mutual
agreement.  Maybe via a TCP option during the handshake?
- A significant increase to the initial window might benefit from
introduction of some form of pacing, since you won't have any ack
clock yet.  This might help reduce losses and delay jitter.

  -John



On Wed, Feb 3, 2010 at 9:28 AM, Lars Eggert <lars.eggert@nokia.com> wrote:
> Hi,
>
> Jerry Chu has recently started the discussion on whether we need to think about tweaking TCP for the "modern Internet." Just came across another presentation from (AFAICT) another corner of Google that makes similar arguments.
>
> FYI: http://sites.google.com/a/chromium.org/dev/spdy/An_Argument_For_Changing_TCP_Slow_Start.pdf
>
> This topic seems to be gaining momentum, and the WG should take some time considering if there is work here for it.
>
> Lars
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