The IPv4 Address Report lists two possible dates for when the number of IPv4 dates will run out: April 17, 2010 or December 2, 2010, depending on the source.
The Internet Assigned Numbers Authority (IANA) predicts the April 17 date. It manages IPv4 addresses, but does not handle things like end-users for ISPs. The Regional Internet Registries (RIRs) is a collection of regional bodies that distributed IP addresses to various areas, and made the December 2, 2010 prediction.
Regardless of whether it's April or December of 2010, the time of reckoning is only three years away. Now the American Registry for Internet Numbers (ARIN), the organization responsible for giving out IP addresses in North America, has published a resolution exhorting the industry to get its tail in gear. ARIN is promoting a rapid move to IPv6 (define)ARIN says that 19 percent of the IPv4 addresses are still available, while 68 percent have been allocated and 13 percent are "unavailable," whatever that could mean. There are 4.3 billion IPv4 addresses, or 2^32. IPv6 has 2^128 addresses, or 16 billion-billion.
There have been efforts to get more mileage out of IPv4 by using tricks like conversions to IPv6 or using duplicate IPv4 addresses within a firewall. This has helped extend the lifespan of IPv4 but it only prolonged the inevitable.
Sam Masud, principal analyst for carrier infrastructure at Frost & Sullivan, warned last year that there could be an IP shortage by 2010. He's not exactly gloating over his apparent accurate prediction, but does say that the new warnings are "dire."
"This is like a three-alarm fire as a wakeup call," he told internetnews.com. "There are steps that can be taken, but the way I looked it, the profusion of intelligent endpoints, IP endpoints, is going to increase IP consumption by the mobility area. It could seriously have an impact in that area. That would be most obvious as far as consumers are concerned."
While the IPv4 shortage could impact emerging markets like China, India and Brazil, Masud said those companies have gone into IPv6 in a big way, since they were not burdened with legacy technologies and were able to get with the newest technologies first.
The U.S. is actually more likely to feel the pinch because it's the most dependent on IPv4 and has the most new devices coming online. The federal government has mandated that by mid-2008 all federal agency backbones should go to IPv6, but Masud said "I'll be very surprised if 20 percent make it by then."
Charles King, principal analyst with Pund-IT, said getting companies to adopt IPv6 comes down to cost, "like so many things in business, it's the degree of hassle involved. If you can get by on what you've got now rather than the expense of moving to a new technology, businesses will take the less painful path," he said.