Since it's a 128 bit number, all you ahve to do is start adding prefixes on. I'll give an example with IPv4.
Say your addy is a standard class B, 140.128.32.96 . If the switch-over is handled right, and it went from, say, 32 bits to 40 bits (add another octet), then your IP addy could be something like 0.140.128.32.96 . Or if you wanted to reserve the 0 for a network ID (old school, but some people still like to do that), then your IP would be 1.140.128.32.96. And so on and so forth.
The difficult part comes in scaling and integrating it properly so that it makes logical sense, but hey, if we have practical nanotech by then, we can do the work. *g* |