----- Original Message -----
From: "John Curran" <jcurran@arin.net>
On Feb 3, 2011, at 2:34 PM, Jay Ashworth wrote:
I strongly suspect that his question is actually "Does ARIN have any enforceable legal authority to compel an entity to cease using a specific block of address space, absent a contract?"
ARIN has the authority to manage its database, and does so according to the community developed policies. This includes changing the entries which designate the address holder, and specify that there is now a new address holder.
None of this has to do with how entities configure their routers or servers.
Sure it does. If best common practice is for network operators to get address space from ARIN, and someone gets a block from you that you've supposedly adversely taken back from, say, Goldman Sachs, and starts using it, then *someone* is going to drink your milkshake, whether it be the new user or the old one. There is some reasonable expectation that if you claim to be the Source of All Good (Address) Bits, and you hand out a block that's in dispute, that whomever relied on that will have an action. It's an unpleasant position to be in, but you *are* there, make no mistake. Cheers, -- jra