From owner-freebsd-hackers  Fri May 26 12:33:44 1995
Return-Path: hackers-owner
Received: (from majordom@localhost)
          by freefall.cdrom.com (8.6.10/8.6.6) id MAA05106
          for hackers-outgoing; Fri, 26 May 1995 12:33:44 -0700
Received: from cs.weber.edu (cs.weber.edu [137.190.16.16])
          by freefall.cdrom.com (8.6.10/8.6.6) with SMTP id MAA05099
          ; Fri, 26 May 1995 12:33:42 -0700
Received: by cs.weber.edu (4.1/SMI-4.1.1)
	id AA27641; Fri, 26 May 95 13:26:03 MDT
From: terry@cs.weber.edu (Terry Lambert)
Message-Id: <9505261926.AA27641@cs.weber.edu>
Subject: Re: Drivers for FORE systems cards under FreeBSD
To: phk@ref.tfs.com (Poul-Henning Kamp)
Date: Fri, 26 May 95 13:26:03 MDT
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
X-Mailer: ELM [version 2.4dev PL52]
Sender: hackers-owner@FreeBSD.org
Precedence: bulk

> > 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.
> 
> It's certainly not an argument against ATM...

Poul's right.  It's an argument against bandwidth overcommit.

Which is an argument against non-virtual circuit transports for virtual
circuit traffic.

THAT's the argument against ATM.

On the other hand, ATM and Frame Relay source quench doesn't really
work well with TCP/IP, since TCP/IP doesn't recognize it as a valid
congestion control mechanism.  Arguably, the problem is in TCP/IP.

Except it came first.


					Terry Lambert
					terry@cs.weber.edu
---
Any opinions in this posting are my own and not those of my present
or previous employers.