I've been slowly working on a method of reducing ipV4 table sizes in the core routers. I don't want to go into details of exactly how this will work right now (It's irrelevant to the question I'm going to ask) but it would reduce the number of routes in the global routing table to under 2000. I'm to the point that I need to clean up my notes, put it into RFC-format and submit it as a draft, but before I go through all that work, I generally was wondering if those of you who actually run the "core" networks see a need for something to significantly reduce the table size. The method I'm working on has the following "features". 1) Transparent to "end nodes" - no renumbering, no software changes 2) Software changes are confined to the "defaultless" routers. 3) Software changes are easy to implement - Someone who knows the router OS code well should be able to implement in a week or so, or a month at the most. 4) Low CPU impact - shouldn't impact the "core" router CPUs at all. "Customer Border" routers will have a minor impact - no more than IP filtering or some similar feature. 5) IPv4-specific. I'd go into more detail, but I don't want to waste everyone's bandwidth.