Re: Start accepting longer prefixes as IPv4 depletes?

[Robert Bonomi <bonomi () mail r-bonomi com>]

> From nanog-bounces+bonomi=mail.r-bonomi.com () nanog org  Wed Dec  8 15:36:44 2010
> Date: Wed, 08 Dec 2010 15:34:47 -0600
> From: Jack Bates <jbates () brightok net>
> To: David Conrad <drc () virtualized org>
> Subject: Re: Start accepting longer prefixes as IPv4 depletes?
> Cc: NANOG list <nanog () nanog org>
>
> On 12/8/2010 3:12 PM, David Conrad wrote:
> > Cameron,
> >
> > On Dec 8, 2010, at 12:01 PM, Cameron Byrne wrote:
> > > I believe a lot of folks think the routing paths should be tightly
> > > coupled with the physical topology.
> >
> > The downside, of course, being that if you change your location
> > within the physical topology, you have to renumber.  Enterprises have
> > already voted with their feet that this isn't acceptable with IPv4
> > and they'll no doubt do the same with IPv6.
> >
> > > In a mature IPv6 world, that is sane, i am not sure what the real
> > > value of LISP is.
> >
> > Sanity is in the eye of the beholder.  The advantage a LISP(-like)
> > scheme provides is a way of separating location from identity,
> > allowing for arbitrary topology change (and complexity in the form of
> > multi-homing) without affecting the identities of the systems on the
> > network. Changing providers or multi-homing would thus not result in
> > a renumbering event or pushing yet another prefix into the DFZ.
>
> I think the issue, and correct me if I'm wrong, is that LISP does not 
> address issues of traffic engineering? A lot of the additional routes in 
> DFZ are there specifically to handle traffic engineering.

The primary thing that a LISP-like approach accomplishes is the 'de-coupling"
of infrastructure and leaf networks.  You can mess with either one, w/o
having any effect on the other.