Less than five percent of the world's IPv4 addresses remains free, according to the representative of the five regional internet registries.
The Number Resource Organization (NRO) noted on Monday that the available IPv4 resources dipped below 10 percent just nine months ago and that, since then, 200 million addresses have been allocated. The NRO said that, given the rapidly decreasing numbers of IPv4 addresses, the shift to IPv6 was crucial.
"This is a major milestone in the life of the Internet, and means that allocation of the last blocks of IPv4 to the [regional internet registries] is imminent," NRO chief Axel Pawlik said in a statement. "It is critical that all Internet stakeholders take definitive action now to ensure the timely adoption of IPv6."
The NRO predicted that, at current depletion rates, the last five blocks of IPv4 addresses will be allocated in early 2011, and warned that a last-minute "chaotic scramble" for IPv6 addresses "could increase Internet costs and threaten the stability and security of the global network".
IPv6 addresses are longer and therefore far more plentiful — trillions rather than the 4.3 billion IPv4 addresses in existence — than their predecessors. This quantity is needed not only because of the expanding web, but also because of the explosion in the numbers of other connected devices such as phones and other consumer electronics.