On Oct 20, 2010, at 11:24 AM, Jeroen Massar wrote:
The problem with that is indeed in that little part about "aren't using them", if even only 50% is in use because one allocated it quite sparsely you won't be able to quickly clean it up and return it.
Correct. It might make sense to do so, if you could recover the costs of the work involved. This is the reasoning behind the Specified Transfer policy that was recently adopted; it allows (once we're at depletion) for parties to free up address space and get compensated. It's goal is not to provide a windfall for those holding unused space; in theory, those with unused address space should be returning it already if they can easily do so.
One can of course wonder if they are supposed to use that or not. The fact that they do not have reverse DNS delegation for it says quite a bit already of course.
One of the other benefits of improved utilization for returned space is less space which is "sitting idle" and available to be hijacked. /John John Curran President and CEO ARIN