On Feb 9, 2009, at 2:11 PM, Ricky Beam wrote:
On Sat, 07 Feb 2009 14:31:57 -0500, Stephen Sprunk <stephen@sprunk.org> wrote:
Non-NAT firewalls do have some appeal, because they don't need to mangle the packets, just passively observe them and open pinholes when appropriate.
This is exactly the same with NAT and non-NAT -- making any anti-NAT arguments null.
And making the PRO-NAT arguments in this respect equally NULL. This was being touted as a benefit of NAT, not a reason not to do NAT. Your statement proves my point... It is NOT a reason to do NAT or a benefit derived from NAT.
In the case of NAT, the "helper" has to understand the protocol to know what traffic to map.
In the case of a stateful firewalling ("non-NAT"), the "helper" has to understand the protocol to know what traffic to allow.
Subtle difference, but in the end, the same thing... if your gateway doesn't know what you are doing, odds are it will interfere with it. In all cases, end-to-end transparency doesn't exist. (as has been the case for well over a decade.)
Right. This is the counterpoint to the argument that NAT is needed. You have now agreed that it is not. Owen