The Long Slow Death of IPv4
Years after the end of the free pool of IPv4 addresses, IPv4 is still very much alive.
Last week my inbox got flooded by PR comments about how the Internet was running out of addresses, as ARIN (American Registry of Internet Numbers) and its public relations people were warning about IPv4 address availability.
It's a story I've heard (and written) before.
In February of 2011, there was an official ceremony in Miami that was supposed to mark the end of IPv4. At that time, ARIN and others declared that the free pool of available IPv4 addresses were officially depleted.
Yet here we are four and half years later and IPv4 is very much alive and ARIN is still warning about the final days and lack of IPv4 availability.
What's going on?
As it turns out, that's also a story I've already written, five years ago when I met with ARIN's CIO in Toronto back in 2010. At the time, ARIN explained to me the process that would mark the last days of IPv4. Basically it's a dwindling numbers game, and as ARIN's own pool of available IPv4 addresses declines, the group will only be able to give out increasingly smaller blocks.
As of today's date, ARIN only has 0.00766 of a /8 block left. A /8 block contains 16,777,214 addresses. So that means that ARIN has only approximately 128,000 or so IPv4 addresses left to allocate.
Considering that most organizations and ISPs today widely use NAT (Network Address Translation) to hide multiple devices behind a public IP, those 128,000 addresses could represent a vastly larger number of actual users and devices.
Going a step further, there are multiple organizations, including the IPv4 Market Group, that have IPv4 address space for sale to those who need it.
So here were are, years after the end of the free pool of IPv4, and we're still talking about the end of IPv4 and the need to move to IPv6. IPv4's death throes will continue for years to come, as there is no "flag day," no end date for IPv4. Rather, this is a transition that will take many more years to happen in an organic, evolutionary manner, rather than any epoch-ending event.
Sean Michael Kerner is a senior editor at Enterprise Networking Planet and InternetNews.com. Follow him on Twitter @TechJournalist.