Subject: [lisp] Issue Title (number): Cache Lookup Performance (39)

From: Darrel Lewis <[email-masked]>
Date: Tue, 20 Jul 2010 14:13:14 -0700

Issue Title (number):  Cache Lookup Performance (39)
Draft Section: 4.1 and 6
Issue Description: Cache management

Comments:

Section 4.1 point 2 (same remark applies to Section 6) misses an
important aspect how the mapping is performed the first time a new
destination EID is seen at ITR and how subsequent maps are
performed. It seems that a) EID-to-RLOC Cache must be first entirely
scanned for each incoming packet at ITR (not only the first one) and
then if there is no entry i) Data probe i.e. copy the destination EID
value in the destination RLOC field (for LISP 1.5) or ii) originate a
Map Request; otherwise use the corresponding RLOC value in the
retrieved entry as destination RLOC. Needless to say that the delay is
proportional to the number of entries in the cache. Nothing is being
said if the cache is full (which entry should be replaced i.e. the
least frequently used, the least recently used, or the least recently
replaced entry). 

Response:

Dear Dimitri

Thank you for your contribution to draft-ietf-lisp-06.txt. The draft authors have reviewed your comments but do not feel that changes to the document are warranted at this time.  In this case we'd like to leave the details of caching design up to the implementers.   Please feel free to continue discussion of your issue on the LISP working group mailing list, [email-masked]. Should discussion result in WG consensus that changes are required, the authors will incorporate appropriate text into a future version of the draft.

	Thanks!
	Darrel, for the LISP document authors