On Apr 18, 2011, at 12:18 PM, Jeff Wheeler wrote: > 2011/4/18 Lukasz Bromirski <luk...@bromirski.net>: >> LISP scales better, because with introduction of *location* >> prefix, you're at the same time (or ideally you would) >> withdraw the original aggregate prefix. And as no matter how >> you count it, the number of *locations* will be somewhat >> limited vs number of *PI* address spaces that everyone wants > > I strongly disagree with the assumption that the number of > locations/sites would remain static. This is the basic issue that > many folks gloss over: dramatically decreasing the barrier-to-entry > for multi-homing or provider-independent addressing will, without > question, dramatically increase the number of multi-homed or > provider-independent sites. > Done properly, a multi-homed end-site does not need to have its own locator ID, but, could, instead, use the locator IDs of all directly proximate Transit ASNs.
I don't know if LISP particularly facilitates this, but, I think it would be possible generically in a Locator/ID based system. > LISP "solves" this problem by using the router's FIB as a > macro-flow-cache. That's good except that a site with a large number > of outgoing macro-flows (either because it's a busy site, responding > to an external DoS attack, or actually originating a DoS attack from a > compromised host) will cripple that site's ITR. > The closer you move the ITRs to the edge, the less of an issue this becomes. > Owen