From: Greg Skinner <gds(_at_)best(_dot_)com>
My general (cynical) opinion of NAT and other proxy technology is that
the marketplace spoke louder than the voices of the architectural
purists. (No offense intended.) However, given recent changes in the
economic climate, perhaps things will head in the opposite direction.
NAT could also be tempting for some ISPs, becuase that way they will
have captive clients. Anything not especially allowed by the NAT
boxes, must be separately orderd from the ISP (for example, client
cannot send directly mail out to destination based on MX records, they
have to buy mail relaying from ISP).
But, I guess the "marketplace" is the ISP's, not the individual
clients, who don't know what they might miss.