Re: How NAT reacts on table flood ?

From: Bob Middaugh (bob.middaugh@comcast.net)
Date: Tue Jul 11 2006 - 14:52:19 EDT


Use FreeBSD. I've scanned aggressively with several nmap processes running, with no problem at all....and that box also does stateful packet inspection.

 -------------- Original message ----------------------
From: "Robert E. Lee" <robert@dyadsecurity.com>
> On Tue, 11 Jul 2006 15:15:12 +0200
> "Norbert François" <norbertlike@gmail.com> wrote:
> > I was wondering how the NAT reacts when its translation table is
> > full... For example, suppose that you've 100 computers behind a NAT
> > (University) and one (or more) of them engages purposely a lot of
> > connexion, in order to fill the NAT table, what will occur ?
>
> It will no longer complete new connections. In most cases the already
> established connections will continue to function, but in some cases the device
> will stop passing traffic altogether.
>
> Pretty easy to replicate this one from home if you have a linksys/smc/whatever
> nat box at your house, grab your favorite port scanner and scan the internet at
> a high speed. It should kill your NAT box rather quickly as it has to account
> for connection status for every attempted connection.
>
> Robert
>
> --
> Robert E. Lee
> Chief Information Officer
> http://www.dyadsecurity.com
>
> phone: (949) 394-2033
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Concerned about Web Application Security?
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you need to proactively protect your applications from hackers. Cenzic has the
most comprehensive solutions to meet your application security penetration
testing and vulnerability management needs. You have an option to go with a
managed service (Cenzic ClickToSecure) or an enterprise software
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help you: http://www.cenzic.com/news_events/wpappsec.php
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