[rrg] Map and Encaps

[Scott Brim]

Excerpts from Noel Chiappa on Wed, Dec 10, 2008 09:23:07AM -0500:
>     > From: Scott Brim <swb at employees.org>
> 
>     > A LISP EID names a network attachment point. 
> 
> Well.... sort of. (And there are two kinds, IPv4 EIDs and IPv6 EIDs.) What
> the IPv4 EID really names is whatever a vanilla 'IPv4 address' names, which
> is somewhat ambiguous itself.
> 
> It definitely names an entity with a collection of higher-level protocols and
> their ports (UDP, ICMP, TCP, etc). It also seems to name an interface
> (because to get packets to a different interface on a dual-homed host, you
> need to use a different IPv4 address). This is another 'axis of confusion'
> with IPv4 addresses (which are also muddied on the location/identity axis).

First I admit I wrote too quickly, because an EID might be
virtualized.  We may be disentangling identifier and locator but we
still will not have disentanbled locator and "forwarding directive".

Second, the reason I said it names a network attachment point is that
from the point of view of the network -- which is what matters here --
it knows attachment points, not stacks or interfaces.  But that's a
nit.