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Date: Mon, 03 Feb 2003 15:45:12 +0100
From: "Carlos Velasco" <carlosev@newipnet.com>
To: "Alan Cox" <alan@lxorguk.ukuu.org.uk>, "Andi Kleen" <ak@suse.de>
Cc: "Linux Kernel Mailing List" <linux-kernel@vger.kernel.org>
Subject: Re: 2.4.20 Broken Path MTU Discovery?
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On 03/02/2003 at 13:42 Alan Cox wrote:

>The real problem and the reason you have to stop at some point and say "no 
>way" is that third parties can send spoof icmps and force the connection
>down to stupid sizes otherwise. Forcing a BGP feed down to 68 bytes MTU
>tends to knock ISP's off the net for example.

Problem is that the parameter is not documented in filesystems/proc
Also, it is not so easy to send spoofed icmps as the icmp must contain the original packet with high len that caused the icmp.

Regards,
Carlos velasco




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