Seems to me like the logical place to start renumbering, if that's going to be forced, is by outlawing new CIDR block exceptions - if you switch providers you renumber. It's a hateful approach in that it raises the barrier to new providers entering the market, but it's more understandable to customers. The next step would seem to be outlawing *existing* CIDR block exceptions. Give up your portable numbers and get back under the provider's umbrella. We renumbered a group of machines by hand once. Not an experience any of us want to repeat. Flag Day turned into Flag Week! At least if you're switching to another provider you have the chance of running with two addresses on each machine for a month or two. Has a chance of being managed less disruptively. Would be nice if everybody supported DHCP. Reprogram the server then go shut off the main circuit breaker ;-) Anybody care to bet when that will actually happen? Ugh. Renumbering is *NOT* going to be popular. -- Walt