P.S.: Curtis Villamizar had another interesting approach
which involved pushing content far afield to
machines with the same transport-layer (IP)
addresses, relying upon closest-exit routing to
connect one to the topologically-closest replication
machine. Unfortunately, while this could be really
cool for NSPs to offload stuff towards peering
points (public or private), it also has some poor
scaling properties and is uncomfortably reliant
upon the stability of routing.
If he's done any more thinking about the idea,
I'd love to hear about it though.
I don't know about Curtis, but others have solved this problem
(in theory) recently.
We at Net Access have figured out a way (we believe) to get
around the stability-of-routing issue for already-established
TCP sessions in the above approach (multiple machines with the
same IP externally, plus an internally different IP, each
running gated to announce their /32(s) to your IGP) -
hint: a question I asked on NANOG a few days back -
And Alec Peterson (now of Erols) has figured out an even
arguably slicker way to do it.
I'll see if Merit wants to have Alec and I do a presentation
on the methods @ NANOG.
We should be able to implement our various solutions by then...