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 From:  Chris Buechler <cbuechler at gmail dot com>
 To:  M0n0wall <m0n0wall at lists dot m0n0 dot ch>
 Subject:  Re: [m0n0wall] No carrier for WAN
 Date:  Sun, 12 Sep 2004 20:33:41 -0400
On Sun, 12 Sep 2004 16:14:55 -0700 (PDT), Fred Wright <fw at well dot com> wrote:
> Do 10/100 hubs even have autonegotiation?  Since the typical 10/100 hub
> consists of an "overlay" of a 10Mb hub and a 100Mb hub with a single speed
> converter between them, it seems like a "natural" for "parallel
> detection".  Especially since deciding duplex mode is a non-issue with a
> hub.

Good point, it might be.  I haven't a clue how it works on a hub.  

> Because it "successfully" autonegotiated full-duplex mode with a hub, or
> because it has a screwed-up duplex default for the non-AN case?  There
> have certainly been some cases where overriding AN was needed as a
> workaround for a coding bug, but that's different from saying that it's a
> necessary feature with properly working code.

Not sure, where I ran into this the most was on Windows 2000 Server
boxes, on new IBM servers (Intel NIC's) on Nortel 10/100 hubs.  That
was about a year ago, and about 10% of them would assume full duplex
(though the environments were all virtually identical).

> In this day and age, who in their right mind would even bother with a hub
> other than for packet capture? :-)


In an ideal world, I'd just rip all that junk out.  The place I've run
into them en masse is a school district that's a client of my
employer.  They're one of the top 30 biggest school districts in the
US, so replacing all their 10/100 hubs would cost around $10 million
USD (or so they calculated, with labor costs and everything).  They
have around 20,000 machines in a couple hundred locations.  Since
what's there works (sorta... hehe), they have other priorities with
their budget.

I've run into the same at not for profit organizations.  

In a for profit company, I'd pull it all.  :)  It doesn't make sense
to keep that stuff around anymore.