2010 in IP addresses: 225 million down, 496 million to go
As of January 1, 2011, the number of unused IPv4 addresses stands at 495.66 million. Exactly a year earlier, the number of available addresses was 721.06 million. So we collectively used up 225.4 million addresses in 2010. 242 million, really, if we ignore the unusual circumstance that Interop gave back nearly 17 million addresses.
At first glance, this suggests that we have two more years of IPv4 addresses left. But it's not that simple: Asia is almost certainly going to run out before year end. And that means really running out, as in: sorry, no addresses for you. This is different from the depletion of the IANA global pool, which will very likely happen later this month. That event is more like an office running out of those big water bottles in the storage room: every water cooler gets its last bottle and everyone can still drink—for a little longer.
A few days ago, I heard an interviewer on the radio say that the current population of the planet is 6.9 billion, and we'll be reaching 7 billion later this year. The expert he was speaking to immediately corrected him, explaining that the current population of the world is 6,934.196 million people—plus or minus a margin of many millions. So you'd think we have a better handle on the number of IP addresses out there—it's not like new ones are getting born in rural Africa, outside the purview of those who care about such things. And to a large degree, you'd be right: the five RIRs (Regional Internet Registries) publish a snapshot of what they've given out each day on their FTP servers. Despite that, there is still a lot that remains unclear.
