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From: dnc@Strata.COM (David Cornejo)
Message-Id: <9505261855.AA22422@elm.>
Subject: Re: Drivers for FORE systems cards under FreeBSD
To: phk@ref.tfs.com (Poul-Henning Kamp)
Date: Fri, 26 May 1995 11:55:55 -0700 (PDT)
Cc: imb@scgt.oz.au, hasty@netcom.com, julian@ref.tfs.com, pss@fore.com,
        announce@FreeBSD.org, hackers@FreeBSD.org, rv@fore.com
In-Reply-To: <199505261606.JAA01495@ref.tfs.com> from "Poul-Henning Kamp" at May 26, 95 09:06:05 am
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Poul-Henning Kamp wrote:
> > > No promises over here but I am going to try to remedy the ATM situation.
> > > Nor I am going to state who am I going to be dealing with .
> > 
> > Much as I hate generalisations .. I would warn that ATM and IP apparently do
> > not mix well in cases where good interactive response is critical, at least
> > in my limited experience. I get better response over my own overworked 14k4
> > modem connection to the net than over a (university based) 2 megabit ATM
> > link.
> 
> This is not a general problem with ATM, and I tend to say that it's
> because there are other users on the 2Mb ATM than you.

A well configured and not over-stressed ATM link should give you
better performance than what you're getting.  There are unfortunately
a lot of problems that can really screw up IP over ATM.  Check out the
discard rate on cells - if one cell out of a frame gets discarded,
then the whole frame is lost, so if your discard rate gets to be close
to or more than the average number of cells per frame, then very
little or nothing can get through.

-- 
Dave Cornejo                                      voice 1.408.494.2805
StrataCom, Inc.
San Jose, California                             email: dnc@Strata.Com