nanog mailing list archives

Re: Security gain from NAT


From: "Stephen Sprunk" <stephen () sprunk org>
Date: Wed, 6 Jun 2007 10:59:39 -0500


Thus spake "Roger Marquis" <marquis () roble com>
I, for one, give up. No matter what you say I will never
implement NAT, and you may or may not implement it if people
make boxes that support it.

Most of the rest of us will continue to listen to both sides and
continue to prefer NAT, in no small part because of the absurd
examples and inconsistent terminology NATophobes seem to feel is
necessary to make their case.

The thing is, with IPv6 there's no need to do NAT. What vendors have (so far) failed to deliver is a consumer-grade firewall that does SI with the same rules on by default that v4 NAT devices have. Throw in DHCP PD and addressing (and renumbering) are automatic. This is simpler than NAT because no "fixup" is required; a v6 firewall with SI and public addresses on both sides just needs to inspect packets, not modify them.

The same device will probably be a v4 NAT device; nobody is trying to take that away because it's a necessary evil. However, NAT in v6 is not necessary, and it's still evil.

S

Stephen Sprunk      "Those people who think they know everything
CCIE #3723         are a great annoyance to those of us who do."
K5SSS                                             --Isaac Asimov



Current thread: