From owner-freebsd-net  Fri Dec 31 11:11:53 1999
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To: Fernando Ariel Gont <fgont@softhome.net>
Cc: DRHAGER@de.ibm.com, freebsd-net@FreeBSD.ORG
Subject: Re: ARP makes a LAN "vulnerable"? 
In-Reply-To: Message from Fernando Ariel Gont <fgont@softhome.net> 
   of "Fri, 31 Dec 1999 00:19:14 -0300." <.19991231001314.009e7780@pop.softhome.net> 
Date: Fri, 31 Dec 1999 14:11:43 -0500
From: Mitch Collinsworth <mkc@Graphics.Cornell.EDU>
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>I didn't mean to have two machines with the same address. I meant that I could
> use ARP so that the IP address of a given host is translated to the hardware 
>address of MY host. In that way, the packets that someone wants to send to the
> former host, would go to MY host, instead...

Yes, but only for hosts on your local LAN, not beyond the closest router.
And the other host will still be ARPing it's own address at the same
time, so you will end up confusing the other system over which is the
right MAC address for that IP.  Then your local network administrator
will come visit and cut your fingers off.

-Mitch


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