Rate of growth on IPv6 not fast enough?

> What makes you think that not using NAT exposes internal topology??

Or that internal topology cannot leak out through NAT's ? I have seen
NATed enterprises
become massively compromised.

NAT allows people to become far too lazy. Your typical NAT allows
connections outbound, typically configured without any audit trail,
etc., so once a bad guy is inside the "secure NAT firewall," they're
free to connect out to the 'net.

In comparison, an actual real firewall can prohibit {most, all}
outbound access and force the use of proxies. Proxies can provide
logging, content scanning, etc., services.

Many times, those who argue in favor of NAT as a "firewall" are the
same ones who seem to actually be relying on the NAT as inbound
protection, but who aren't really doing anything to control their
outbound traffic, or IDS, etc.

... JG