In Three Years, the Internet Hits a Brick Wall

In an estimated three years or so, the Internet will run out of the IPv4 addresses that it is currently based upon, forcing a transition over to a next-generation IPv6 address scheme – or a halt to all new domains.

That prediction was made last month by the Organization for Economic Co-operation and Development, which told attendees of a worldwide meeting in South Korea that the current address space would run out in 2010 or 2011.

That estimate, in turn, was based upon a Web algorithm that pegs the date at which the Internet Assigned Numbers Authority (IANA) will run out of unallocated Internet addresses, or about Jan. 18, 2011. After that, the estimate is that the first regional Internet registry (RIR), such as the American Registry for Internet Numbers would run out of addresses and be unable to find another on or about Jan. 5, 2012.

At that point, barring some other solution, the Web would essentially be limited to the existing number of domains and sub-domains. The shift to IPv6, however, is seen as a way to escape.

Web addresses such as PCMag.com translate to IP addresses like 96.17.8.27, the actual address for the server on the Internet; the Web address is simply an easier way to remember the numerical address, like 1-800-DOMINOS can be used to quickly call for a pizza.

The problem is that every router and server requires its own unique IP address. As more and more are added to the Internet, the available pool of IP addresses decreases. Gadgets like Microsoft's Zune, which includes a Wi-Fi connection, simply contribute to the "Internet of things" that also require their own IP addresses.

The 32-bit IPv4 address space allows for a theoretical 4.2 billion IP addresses. A 128-bit IPv6 address scheme allows for 2E128 addresses, or "340 billion billion billion billion" addresses. But neither scheme is compatible with the other, making the transition an extremely complicated matter.

In June, the OECD issued its Seoul Ministerial Declaration, a report and call to arms about the impact of changes to the Internet's structure, and their economic effects. "It also calls upon governments and industry to accelerate the transition from IPv4 to IPv6, thus providing a solution to the address space problem as we indeed risk falling short of internet addresses within 3 years, a situation which the "Internet of things" will further deteriorate," said Viviane Reding, a member of the European Commission responsible for Information Society and Media. "Three weeks ago, the European Commission actually set the target that 25% of European internet users should be able to connect to the IPv6 internet by 2010. We will be pushing for it, notably by encouraging public services and leading websites to move faster to IPv6."

The problem is that as the shortage of IPv4 issues becomes more broadly publicized, a "run" on the remaining addresses becomes a possibility.

"This is perhaps a very conservative projection of a date for the exhaustion of the current address allocation policies," the author of the "Potaroo" algorithm, Geoff Huston, who serves as the chief scientist of APNIC, the RIR overseeing Asia and Australia, wrote. "Its [sic] probable that an industry response to this forthcoming situation is one of increasing levels of demand for the remaining unallocated address resources, given the impetus of a "last chance rush" on the registries. If such a run on the unallocated address pool eventuates, and industry players bring forward their requests for additional address space, it is possible that this unallocated address pool exhaustion date may occur sooner than the model studied would apparently indicate."

A corresponding study by Tony Hain of Cisco in 2003 concluded that the IPv4 address pool would be exhausted anywhere between 2009 and 2016, depending upon the forecast model chosen. He added one caveat, however: "Although a longer lifetime projection helps to avoid short-term panic, it can mislead people into believing there is substantial time to worry about this later, resulting in a much bigger problem when reality blindsides everyone sooner than they expected." Next: What to Do?