Hi, NANOG. Something's just struck me: every IPv4 allocation over a certain threshold has a monetary cost (sometimes in the tens of thousands of USD) and according to our RIR, the first equivalent IPv6 allocation is given as a freebie (to encourage migration). (Disclaimer: I'm on the Dark Continent of Africa) So once the "early" adopters migrate their networks to IPv6, there is no business need to maintain the IPv4 allocation and that will be returned to the free pool, since Business would see it as an unnecessary cost. This would seem to counteract the forced move to IPv6, since, once the early adopters move their services exclusively to IPv6 (or maintaining very small IPv4 blocks), there would be plenty of IPv4 space for the late adopters to request (after the RIR quarantine period, etc). Naturally, 6to4 functionality must remain for a while to interoperability reasons, so their resources would be available to the IPv6 world for time to come. Unless I'm misunderstanding the RIRs policy regarding IPv4 allocations; has it been stated by all RIRs that IPv4 blocks are unallocatable once the exhaustion phase kicks in? Or is there another mechanism to ensure that we don't hand out the space being handed back once IPv6 is the norm? :) Regards, -H.