IPv6 took a significant step forward this week with ICANN's decision to officially add add the next generation protocol to its root server systems. The shift to IPv6 is perhaps the largest and most significant change to the structure of the internet in decades - ICANN's move a signal that the revolution has officially begun.

In 2001 and long before, there were endless streams of media warnings that wireless technology (and smart refrigerators) were gobbling up the world's allocation of IP addresses, particularly in Europe and Asia, where fewer addresses had been dished out. As of 2002, the U.S. operated more than 3,012,735,145 IP addresses, whereas China and South Korea were originally allocated 38,527,336 and 23,559,640 IP addresses respectively, despite having a significantly larger combined population (1.3 Billion plus).

To solve this problem, the push grew louder in 2002 and 2003 to get IPv6 out of the testing phase and into practical circulation. That push came largely from foreign countries, who blamed the United States for delaying their cooperation - due primarily to their abundance of IP addresses. With the explosion of wireless services, the US was forced to accept the reality of the situation and quicken its pace of adoption.

In 2003, the Pentagon put the shift to IPv6 on the front burner, launching a new five-year migration agenda; claiming that full military migration should be completed before 2008. Cooperatively the Government and Academia also launched the MoonV6 project, the largest IPv6 network to date. The network has created a functioning test-bed to help iron out upgrade issues before the technology hits the public internet bloodstream.

As with any technology, IPv6 isn't without its critics, however. Researchers at MIT this past January suggested (Technology Review, registration required, use Bugmenot) that the migration from 32 to 128 bit addresses would leave the web "slower and less secure".

The claims of IPv6 being "slower" made by MIT are based on the idea that V4 routers would have to process the new addresses in software, something that's made irrelevant as hardware is slowly upgraded. The article also claims (without much support) that the "nail in the coffin" for IPv6 could be the elimination of NAT (Network Address Translation). NAT ironically has allowed this shortage of IP real estate to be less noticeable by allowing multiple devices to hide behind a single address. Both MIT claims were hotly debated.

According to comments made by ICANN's chief Vint Cerf to Reuters today, two-thirds of the world's 4.3 billion Internet addresses are currently in circulation, and the shift toward IPv6 should increase capacity some "25,000 trillion trillion times." Cerf claims IPv6 will run parallel to IPv4 for about 20 years in order to work out the assorted kinks and bugs.

Users interested in learning or talking about IPv6 should stop by our IPv6 forum.