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Date: Tue, 8 Jul 2003 20:08:08 -0500
From: Dan Nelson <dnelson@allantgroup.com>
To: Brent Wiese <brently@bjwcs.com>
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Subject: Re: NAT and MTU
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In the last episode (Jul 08), Brent Wiese said:
> I have a machine that is being double-NAT'd.
> 
> Would it make sense to set the MTU lower to account for the NAT
> overhead?
> 
> It makes sense to me as I know MTU, but I like to check in case my
> thinking isn't right. :)

There is no overhead; all NAT does is rewrite IP addresses in the
header (and in some data packets of certain protocols like FTP).  It
adds no extra data.

-- 
	Dan Nelson
	dnelson@allantgroup.com