Bad things will happen when we run out of iPv4 addresses

You might have read about how the long-warned end of available IPv4 address space is a bit more imminent than it was, as the IANA, which governs IP address allocations on the Internet, has run out of IPv4 addresses to allocate. Simply stated: The IPocalypse is coming! It's not going to be the end of civilization, or even just the Internet, as we know it, but there will be some big problems. We're not prepared for them and we're not even working all that hard on preparing.

Here's what we know will happen in the short term: There are 5 RIRs (Regional Internet Registries) for different parts of the world -- AfriNIC, APNIC, ARIN, LACNIC, and the RIPE NCC. These organizations get address blocks from the IANA and dole them out to ISPs and other entities in their regions based on their own policies.

Each of the RIRs still has some IPv4 addresses left, but various models show them starting to run out within about a year. After that, at some point, ISPs will begin to run out. The models are less clear on this. Stephan Lagerholm's ipv4depletion.com calculates that the first RIR to run out will be APNIC (Asia-Pacific Network Information Centre) in 228 days (as I write this), but it has the last RIR depletion date in December, 2016. That may sound odd, but there still are over 500 million free addresses by his calculation and it's not hard to see that these things get consumed faster in different parts of the world.