BBC News: Internet approaches addressing limit

BBC News – Internet approaches addressing limit By Mark Ward, Technology correspondent, BBC News

In less than 18 months there will be no more big blocks of net addresses to give out, estimates suggest.

Predictions name 9 September 2011 as the date on which the last of those tranches is released for net firms and others to use.

Everything connected to the net needs an “IP address” to ensure data reaches the right person or device.

Experts say that the net’s entire existing address space will be exhausted about a year after that date.

A newer scheme is being rolled out but many firms and countries are being slow to switch, experts warn.

Small pool

The net is built around version four of the Internet Protocol addressing scheme (IPv4) which has space for about four billion addresses. Its successor – IPv6 – has trillions available.

The continued growth of the net is tied to this pool of addresses.

While four billion was enough in the 1970s when the net was being set up, the growth of the world wide web is rapidly depleting this store.

The growth of the web has meant that only about 7% of these addresses, roughly 300 million, are left to allocate. This entire pool is expected to be depleted in April 2012.

In early May, the Internet Assigned Numbers Authority (IANA), which oversees the net address space, handed over two of the big chunks of remaining addresses.

The removal of these 17 million addresses from the global pool meant that the date on which there will be no more big chunks left jumped forward.