[139728] in North American Network Operators' Group
Re: Implementations/suggestions for Multihoming IPv6 for DSL sites
daemon@ATHENA.MIT.EDU (Jeff Wheeler)
Mon Apr 18 15:18:57 2011
In-Reply-To: <4DAC8673.5070906@bromirski.net>
Date: Mon, 18 Apr 2011 15:18:46 -0400
From: Jeff Wheeler <jsw@inconcepts.biz>
To: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
2011/4/18 Lukasz Bromirski <lukasz@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.
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.
In addition, the current negative mapping cache scheme is far from
ideal. I've written a couple of folks with a provably superior scheme
(compared to existing work), and have received zero feedback. This is
not good.
> We may of course argue that the current routers are pretty
> capable in terms of processing power for control-plane, but
We agree that the ability to move tasks from the router to an external
control plane is good. BGP may get better at this as time goes on,
too.
--=20
Jeff S Wheeler <jsw@inconcepts.biz>
Sr Network Operator=A0 /=A0 Innovative Network Concepts
