North American Network Operators Group
Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical

Re: Security gain from NAT

  • From: Dave Israel
  • Date: Mon Jun 04 17:05:04 2007



[email protected] wrote:
On Mon, 04 Jun 2007 11:32:39 PDT, Jim Shankland said: 
*No* security gain?  No protection against port scans from Bucharest?
No protection for a machine that is used in practice only on the
local, office LAN?  Or to access a single, corporate Web site?


Nope. Zip. Zero. Ziltch.  Nothing over and above what a good properly
configured stateful *non*-NAT firewall should be doing for you already.


What the firewall *should* be doing? The end devices *should* not need protection in the first place, because they *should* be secure as individual devices. But they are not. So you put a firewall in front of them, and that device *should* give them all the protection they need. But sometimes, it doesn't. So you make end devices unaddressable by normal means, and while it shouldn't give them more security, it turns out it does. No matter how much it shouldn't, and how much we wish it didn't, it does.

The difference between theory and practice is that in theory, there is no difference, but in practice, there is.