Quoting RFC2860 [Re: I-D Action:draft-azinger-scalable-addressing-00.txt]

[David Freedman]

Nick Hilliard wrote:
> On 27/09/2010 23:35, Tony Li wrote:
>> - We use ILNP (or similar) for v6 to decouple locators from identifiers.
> 
> off-topic rambling:
> 
> on the issue of decoupling locator and identifier,  I'm still not really
> sure that any L/I separation is really going to fix our problems in the
> long term.  In fact, we already use a form of locator / identifier
> separation: ASN and prefix.  We could - with some work - implement L/I
> separation by creating a new BGP / core router model which made routing
> decisions on the basis of AS identifier only, and not per-prefix.

Excuse my ignorance on the subject, but I thought the purpose of L/I was
to only route locators on the "internet" and to route "identifiers" (i.e
belonging to services/people) via an overlay (but perhaps I've had my
head in the LISP cloud for a while)

You get a locator and it multihomes, locator aggregation is possible but
not key to the system, the main objective to control the growth in terms
of addressing requirement and punt the services and people to the overlay.

> 
> But I can't help wondering that if we perform our routing decisions
> based solely on locator (e.g. ASN or other) and not identifier, then we
> commit ourselves to trashing our current traffic engineering
> flexibilities.  If we decide we want traffic engineering capabilities
> again, we need to introduce a routing protocol which also discriminates
> on the basis of the identifier.  And that's hardly an improvement on
> what we have right now.

Nothing wrong with mapping identifier services to locator T/E, this
easily achievable in an inspected (but possibly out of band) data plane
model

Dave.

> 
> Nick
> /me goes off to read up on the latest coolness for L/I separation which
> hopefully deal with all these problems
> 


-- 


David Freedman
Group Network Engineering
Claranet Group