Experts say IPv6 is the solution
The entire stock of IPv4 addresses is likely to be exhausted by September 2011.
The final batches of the stock of IP addresses are about to be handed out. After that, each of the five regional agencies that distribute net addresses will get one of the remaining blocks "/8".
A "/8" is the biggest block of net addresses (comprising 16 million addresses) that the central repository the Internet Assigned Numbers Authority hands out.
The addresses in those last five blocks are expected to be exhausted by September 2011.
The distributor of net addresses in Europe RIPE managing director Axel Pawlik said he expected the entire stock to be over in September 2011.
Pawlik added, "If you do not have any plans for IPv6 now you are irresponsible."
At present, the internet runs mostly on IPv4, which provides 4.3bn web addresses.
When these are all assigned to computers, mobile phones and other devices, IPv6 is expected to provide space for many more addresses.
However, IPv6 web addresses may not be accessible from IPv4 devices.
Most internet service providers have not switched to the new protocol. At present, IPv6 accounts for just 1% of web traffic.
Google, Facebook and Yahoo are expected to turn on IPv6 versions of their sites on 8 June 2011.