It’s Time To Let Go Of IPv4

For about 15 years, the Internet authority IANA has been warning that the current version of the Internet Protocol, IPv4, is nearly exhausted. However, according to the latest estimate from RIPE NCC – the Regional Internet Registry (RIR) for Europe, the Middle East and parts of Central Asia – IANA will assign its last batch of IPv4 addresses in June 2011.

IP addresses are unique online identifiers made up of four number groups, allowing computers to communicate with each other around the world. The Internet is built around version four of the IP addressing scheme (IPv4) which can accommodate around four billion addresses.

When the web was set up in the 1970s, four billion seemed like more than enough, but the growth of the Internet – in particular the current surge in demand for mobile Internet – means they are being used up faster than ever.

IPv6 uptake still slow

In the knowledge that the IPv4 system would eventually fall short, the IPv6 standard was developed in the early 1990s, and completed in 1994, when the addresses were first predicted to run out. The new version allows trillions of new IP address combinations, because it uses 128 bits of address data, giving it much greater capacity to accommodate the growth of the Internet than IPv4 addresses, which contain only 32 bits.

However, despite repeated warnings that the IT industry is adding unnecessary risk and complexity to Internet architectures by ignoring the availability of IPv6 addresses, there is still a large number of businesses and ISPs that have not switched over.

According to Axel Pawlik (left), managing director of the RIPE NCC and chair of the Number Resource Organisation, which coordinates the world’s five RIRs, those who put off the inevitable will only create worse problems for themselves in the future.

“For many years we have said you need to go to IPv6, but one day it will be unavoidable that you have to do this. And the sooner you do this the better,” Pawlik told eWEEK Europe. “It’s a little bit cheaper to do it now; It will be more complex to do it later and, of course, you will be under much more pressure to do it quickly, which will give rise to problems.”

“It’s not that the equipment isn’t there or the technology isn’t there, it’s just the act of finally doing it and making plans for doing it in an orderly way that frightens some people away,” he added. “They say we can’t deal with this, it is complex and it is expensive. But people who have done it mostly say it’s not as bad as it could have been.”

Fair distribution of remaining /8s

The way IP address allocation works is that the RIRs are given enormous blocks of IP addresses by IANA, known as /8s, which the RIR’s then break up and distribute among Internet service providers (ISPs) and large corporations.

As stocks of IPv4 addresses began to run out, the five RIRs agreed that they would only ask for a maximum of two /8s at a time, to avoid a ‘gold rush’ for the remaining IP address blocks. “That makes the whole process a little bit more predictable,” said Pawlik.

However, when eventually the last five /8s of IPv4 addresses remain in the global pool held by IANA, the organisation will allocate them automatically to the five RIRs, regardless of whether or not they need more IPv4 addresses at that point. IANA’s site currently shows 16 remaining /8s in the IPv4 address space.