From owner-freebsd-net  Mon Oct  2  7:38: 4 2000
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Message-ID: <39D89D9D.5BB9508C@elischer.org>
Date: Mon, 02 Oct 2000 07:37:17 -0700
From: Julian Elischer <julian@elischer.org>
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To: Luigi Rizzo <luigi@info.iet.unipi.it>
Cc: net@FreeBSD.ORG
Subject: Re: SACK in FreeBSD TCP.
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Luigi Rizzo wrote:
> 
> > Is anyone working on a SACK  (Selective acknowlegement) implementation
> > for FreeBSD?
> >
> > (rfc 2018)
> >
> > It would make a huge difference to performance out here at the edge of the
> > univertse (Perth, Western Australia)
> 
> I wonder if the "huge difference" is for real or just a myth.
> 
> When i did some work on sack back in 1996 (including a FreeBSD
> implementation, see http://www.iet.unipi.it/~luigi/sack.html


great.. I'll look at that..

Julian

> I did not find that SACK to be such a panacea. Basically,
> most connections under high loss still had a tendency to
> stall because the window would never open enough to have 3dupacks
> which would trigger a retransmission...
> 
>         cheers
>         luigi
> -----------------------------------+-------------------------------------
>   Luigi RIZZO, luigi@iet.unipi.it  . Dip. di Ing. dell'Informazione
>   http://www.iet.unipi.it/~luigi/  . Universita` di Pisa
>   TEL/FAX: +39-050-568.533/522     . via Diotisalvi 2, 56126 PISA (Italy)
>   Mobile   +39-347-0373137
> -----------------------------------+-------------------------------------
> 
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-- 
      __--_|\  Julian Elischer
     /       \ julian@elischer.org
    (   OZ    ) World tour 2000
---> X_.---._/  presently in:  Perth
            v


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