From owner-freebsd-security  Thu Mar 22 17:11:53 2001
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From: Olivier Nicole <on@cs.ait.ac.th>
To: ostap@ukrpost.net
Cc: freebsd-security@FreeBSD.ORG
In-reply-to: <3ABA09E0.141711C9@ukrpost.net> (message from ostap on Thu, 22
	Mar 2001 16:19:12 +0200)
Subject: Re: DoS attack - advice needed
References:  <3ABA09E0.141711C9@ukrpost.net>
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>i'm interested in the ways how this can be done, and what is needeed
>to prevent such attacks on 3.x freebsd, without blocking all icmp
>traffic.

One solution I heard about is to limit the bandwidth available for
ICMP (say 5% of your total bandwidth). Of course during a DoS attack
no valid ICMP will get through but at least your network will still be
working.

Regards,

Olivier

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