[cc's reduced to keep Noel's head from exploding :-)]
Yakov, On Jan 22, 2009, at 3:12 PM, Yakov Rekhter wrote:
The question to ask is whether LISP is an appropriate solution to the problems discussed at the IAB's October, 2006 Routing and Addressing Workshop.
That is _a_ question, but not necessarily _the_ question. Perhaps a better question is whether or not experimenting with LISP will provide insights into appropriate solutions.
Concerns with scaling and operational properties of these techniques have been raised many times before (both at the previous BOF, as well as on the RRG mailing list). Yet the LISP proponents still did not adequately address these concerns.
Oddly, I'm reminded of http://ars.userfriendly.org/cartoons/? id=20090125.
Perhaps the reasons LISP proponents haven't adequately addressed those concerns is because they are not addressable with the underlying LISP assumptions? Your criticism feels approximately equivalent to the arguments made against IP by telco folks when they'd list all the ways in which IP violated circuit switching assumptions. The appropriate response is probably along the lines of "well, duh." When you change underlying assumption, you get a different answer with different costs and benefits. TANSTAAFL.
LISP, as with _any_ loc/id approach I am aware of, requires a some form of mapping system to translate locators into identifiers. You can argue about whether you want a pull-based mapping, a push-based mapping, or some hybrid, but it is a fundamental assumption that a separate mapping system exists.
It can be argued that the requirement for a mapping system will doom any loc/id approach (as it was argued that without bandwidth reservation from source to destination any packet switched approach would be doomed), however I, for one, remain unconvinced and hence believe experimentation to find out what the other characteristics of loc/id separation might be is worth the effort.
Regards, -drc _______________________________________________ rrg mailing list [email protected] http://www.irtf.org/mailman/listinfo/rrg
