Re: [lisp] LISP EID Block Size

jnc@mercury.lcs.mit.edu (Noel Chiappa) Thu, 31 October 2013 19:55 UTC

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Date: Thu, 31 Oct 2013 15:54:53 -0400 (EDT)
From: jnc@mercury.lcs.mit.edu (Noel Chiappa)
Cc: jnc@mercury.lcs.mit.edu
Subject: Re: [lisp] LISP EID Block Size
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    > From: Roger Jorgensen <rogerj@gmail.com>

    > The _big_ difference between EID's out there today, and the one from
    > this new netblock are that any system should _know_ by matching the IP
    > that this is EID space, and by that know how to handle it.
    > If traffic grow as everyone predict, and continue todo so, optimizing
    > the handling of LISP EID's is probably a very good idea.

Sure, but realize that there are limits on the improvement of basic LISP
handling.

E.g. if we allocate a large number of PI blocks from a large EID block, an
ITR will likely _still_ have to do a mapping lookup cycle in order to be able
to forward traffic to an PI EID block's ETR. (Since there would be many
different PI blocks allocated from that large PI block, scattered all over
the Internet.)

Yes, the 'interoperation with legacy hosts' part would be better, since there
would only need to be a single large advertisement into the legacy DFZ (as
someone else pointed out).

And who knows, maybe someone will develop a use-case in which 'facial' EIDs
bring more significant benefits. But I think Darrel's point is very accurate:
"we should keep our expectations for the benefits of this block modest".

	Noel