Post-Exhaustion-phase "punishment" for early adopters

[Heinrich Strauss <heinrich () hstrauss co za>]

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.