Allocations for "always-on" ISPs

"Neil J. McRae" <neil at COLT.NET> wrote:
> NAT is your friend - very few home users need real IP addresses.

True, but the problem is logging the NAT translations to track down
abuse cases. Since attacks on other sites will appear to come from
NAT pool address, it's impossible(?) to find out which NAT'd user
had a particular public IP address at a particular time. Sure, you
might know what private IP address they had, but how do you log the
translations?

I think this make it very difficult to justify using NAT in public
ADSL/Cable environments. I've heard that NAT logging is somewhere
on Cisco's roadmap, but until it's available, or some other scalable
NAT logging solution is possible, it looks like public IP addresses
are the only viable option.

Karl