There's always the nice 'n' easy system of using 10/8 and NAT as a provider, making renumbering about 5 minutes work. Even taken to the extreme, it wouldn't take long to change your BGP announcements / have your provider change their BGP announcements / whatever. Nameservers are a bit harder to renumber, but that's not too bad. Wonder how long it'll be before ISPs rather than corporates start to use NAT for most of their network. Karl Denninger wrote : |-> |-> You're right. |-> |-> And as soon as the mainstream hardware we all sell to people, and that has |-> significant market penetration in the installed base, makes this reasonable |-> to do for a *large* operation, this will be reasonable. |-> |-> However, as the state of IPV4 and its hardware sits right now, it is NOT |-> reasonable to do *other than on the boundaries of a customer's individual |-> decision*. |-> |-> That is, if a PROVIDER changes upstream links, it is unreasonable to expect |-> their *customers* to renumber. To force that paradigm is to attempt to |-> tie an ISP to a given provider. The requirement to renumber comes out of th |-> e |-> blue, it is an unanticipated cost, and one which is neither under the |-> control of nor a result of the actions of the customer. |-> |-> Better go talk to some attorneys before you do things that lead to this |-> result. |-> |-> If a *customer* changes providers, they bear the costs of their actions. |-> If the operative cause of their renumbering is their decision to leave one |-> ISP and go to another, *they* are directly responsible for their own pain. |-> |-> THAT is much more likely to pass muster. |-> |-> -- |-> -- |-> Karl Denninger (karl@MCS.Net)| MCSNet - The Finest Internet Connectivity |-> http://www.mcs.net/~karl | T1's from $600 monthly to FULL DS-3 Service |-> | 99 Analog numbers, 77 ISDN, Web servers $75/mo |-> Voice: [+1 312 803-MCS1 x219]| Email to "info@mcs.net" WWW: http://www.mcs. |-> net/ |-> Fax: [+1 312 803-4929] | 2 FULL DS-3 Internet links; 400Mbps B/W Inte |-> rnal |-> I've had a wonderful time... ...but this wasn't it.