When IANA allocated its final set of /8 address blocks, one each to every Regional Internet Registry (RIR) on February 4, 2011, the "source" of IPv4 address space had officially dried up. The second tier in the IP address distribution chain, the Regional Internet Registries (RIRs), at that point each received a /8 of address space (consisting of 16,777,216 IP addresses).
Interestingly, the Asia Pacific Network Information Center (APNIC) RIR received the last allocation that triggered this final /8 distribution to each RIR. The allocation of two /8s to APNIC February 1 left IANA with five /8s left, which by policy were distributed to each RIR. So APNIC received three /8s in early February - as of today, they are down to one. Having allocated address space comprising about 33 million IP addresses in ten weeks is a testament to the voracious appetite for IP addresses in the region. Of course the AP region compasses over two-thirds of the world's population!
At this point the APNIC will institute its final /8 policy or stage 3 policy which provides for smaller maximum allocations to prolong the lifetime of this final /8. Internet Service Providers in the region will soon have no access to additional IPv4 space and their customers will only receive IPv6 allocations, probably by later this year. The onset of the "IPv6-only" customer is fast approaching. Are your Internet servers for www and email prepared to receive their communications?