2001-10-05 01:35:13

by Rob Landley

[permalink] [raw]
Subject: Re: Ethernet Error Correction

On Tuesday 02 October 2001 05:55, Vojtech Pavlik wrote:
> On Tue, Oct 02, 2001 at 11:48:01AM +0200, Pavel Machek wrote:
>
> Well, if you checked all the cables, you'd most likely find the device
> capable of sending the bad CRC frames. Also, if you use a switch (not ha
> hub or coax), it won't work at all.

You can cause a lot of switches to degrate to HUB mode by overloading their
arp cache mac address table thingy. (Fun for packet sniffing when you've got
a card that can change its mac address in software. Send packets originating
from a few thousand different mac IDs and watch the switch throw up its hands
and go "AAAAAH!". Sniffing the right init sequence for a pppoe connection
with nonstandard authentication can be a bit difficult otherwise, with modern
hardware... :)

I haven't tried it on a very wide variety of manufacturer's switches, though.
And I dunno how that relates to CRC behavior...

Rob