> > Putting a crypto-based host identifier in the address is unnecessary, > > since there's really no need to include a strong host identifier in > > every packet sent to a host. The locator alone is usually sufficient, > > and if that's not sufficient, the sender can generally encrypt the > > traffic with a secret known only to the intended destination. > > Putting a 64 bit crypto-based identifier in IPv6 addresses isn't > something that would be done because it's the only way to arrive at > certain functionality, but rather because it's a convenient way to do > it. The 64 bits are present in each packet anyway, and putting a crypto > identififer in each packet is much simpler than thinking very hard > about when one is required, and then find a good place for it. well, you have to do that thinking anyway in order to get multihoming, mobility, and renumbering to work right.