Subject: RE: Some Comments on ID/Loc Separation Proposals

From: "Christian Huitema" <[email-masked]>
Date: Tue, 18 Nov 2003 15:26:40 -0800

> > Wnc> The use of the term "Identifier" or "ID" sweeps an important
> > MWnc> issue under the rug in some cases:  Is this a host ID or an
> > MWnc> interface ID?
> >
> > or a 'stack id' or an 'endpoint id'?  and what do these mean,
> > precisely.
> 
> Exactly,  Noel Chiappa referred to a host/endpoint/stack ID as though
> a host, an endpoint and a stack are all the same thing.  But are they
> really the same thing?  Is there even a 1:1:1 correlation between
> these things?

There are many cases in which topology does matter. The classic example
is VPN: you don't necessarily want a connection initiated over a VPN
channel to migrate to another interface. Another classic example is
compartmented organization, with a secret network and an open network,
where you don't want a secret process to use the open network. 

There are also classic cases of interfaces with different monetary
characteristics, e.g. flat fee versus pay by volume. You don't want
applications assuming a flat fee to accidentally migrate to a pay by
volume interface. 

-- Christian Huitema

---

From: Eliot Lear <[email-masked]>
Date: Tue, 18 Nov 2003 17:04:38 -0800

> where you don't want a secret process to use the open network.

Yes, I would agree that topology does matter.  However, I think your 
example may be overstated.  In fact I *would* like my VPN to migrate 
from one interface to another when I change addresses (outside-outside). 
  I would also like to know when I don't need it because I'm "inside" 
some network.  To me that's a matter of secured signaling to the next layer.

> applications assuming a flat fee to accidentally migrate to a pay by

Righto.  And that's a matter of filtering at the TCP/UDP or even the 
application layer.  Microsoft is in a very good position to ask and 
answer the question, "Who is calling me?"  It's a bit more difficult if 
you're a router, but then IPSEC makes that a pain, anyway.

Eliot