Paul,
This is completely orthogonal to a real identifier/locator split,
which would divide what we know of as the 'address' into two
separate spaces, one which says "where" the node is,
topologically, and one which says "who" the node is.
Hmm, no idea whether it's a good idea or not, but from POV of
scaling while it might make 'where' scaleable, you still have to
find a way to tie "who" to "where".
True. Even better, you get to change this binding (mobility) or have
multiple bindings (multihoming).
Some might say we already have this split though, DNS.
True enough, but unfortunately, it's not done in a way that we can
make use of the identifier in the routing subsystem or in the
transport protocols.
Tony