Nearly a year after the European Union (EU) urged business leaders to embrace version six of the Internet Protocol (IPv6), with alarming warnings that internet addresses were about to run out ­ – and more than 10 years since it was standardised ­ – IPv6 accounts for less than one per cent of internet traffic.

IPv6 has one crucial advantage over IPv4 ­ – a larger addressing space of about 3.4x10^38 static IP addresses, enough to handle rocketing demand for static IP addresses from emerging economies and the growing number of portable devices being connected to the web.

But take-up has to date been meagre. A global survey of more than 1,100 organisations (389 in Europe) conducted in 2008 by the American Registry for Internet Numbers (Arin), found more than half did not currently have any IPv6 address allocation, irrespective of whether they were using them or had done in the past. The only early adopters tended to be concentrated in the education and research and development sectors.

Despite the heavyweight backing, many organisations have little appetite for infrastructure projects, says Rob Bamforth, principal analyst at research group Quocirca.

“If you are there at the coal face, you know that IPv6 needs to be done, and there might be problems if it is not. But there is always a problem justifying infrastructure spend, and right now it is getting harder,” he says. “There are some benefits around cost reduction and being able to handle 10 times the number of IP addresses for all those handheld devices, but that is not necessarily a selling point.”

According to the Arin survey, for 40 per cent of organisations the prime motivation for moving to IPv6 is a desire to get ahead of the game. Significantly, given rumbles about the imminent exhaustion of the IPv4 address pool, only 13 per cent said they believed user demand warranted an IPv6 migration, and just six per cent cited a lack of IPv4 addresses as a motivating factor.

“It is probably more effective to argue the case for IPv6 around better management and risk reduction from improved security and good governance,” says Bamforth. “It offers a way of insulating against the sort of external threats and risks that come from the economic shocks that have affected the banking sector recently.”

But a lack of funding and the difficulty of selling tangible benefits to the board are not the only factors causing IT departments to hold off their IPv6 migration. Many are also nervous of the technology challenges that the transition presents, particularly when it comes to mixing IPv4 and IPv6 on the same infrastructure.

In the Arin survey, 43 per cent of respondents said a lack of dual support for IPv4 and IPv6 at application level was an issue for them, with 24 per cent citing problems with legacy applications.

Router and switch manufacturers have long supported IPv6 in new products, and many have enabled retro-fitting to legacy kit through firmware or software upgrades. But support for dual IPv4/v6 stacks in certain applications remains patchy.

“But that does not mean that all the equipment can do IPv6,” says David Holder, chairman of the IPv6 Taskforce in Scotland.

Many network management and provisioning tools cannot function using multi-protocol operations. In effect, firms are faced with having to run parallel systems, much like analogue and digital television broadcasters, until IPv6 gains sufficient momentum to turn off IPv4. It could be more than a decade before that point is reached.

“If you run IPv6 and IPv4 concurrently, you might need to add more memory to the router, for example, and there could be other cost implications depending on how recently you bought the hardware,” says Holder.

The fact that most IT professionals remain unfamiliar with IPv6 and how to manage and implement it has also stalled adoption. Of those polled for the Arin survey, some 39 per cent cited a lack of IPv6 expertise as an ongoing problem for the protocol’s adoption.

“IPv6 skills and knowledge are in short supply, despite the fact that all the network staff and strategy people will need to learn about the differences in the way it works,” says Holder. “Lots of people have grown up with network address translation (NAT) and do not remember that the internet originally worked without it.”

NAT allows organisations to modify network address information in the data being transmitted over the internet, remapping one address into another. This has been used to overcome the limits on IP addresses within IPv4.

Quocirca’s Bamforth says that, rather than having to rely on external trainers, vendors should do more to educate customers about the benefits of IPv6 and help them with their upgrades.

“It should be getting easier to find IPv6 training, but it is up to the equipment suppliers to schedule an upgrade path and provide the right tools and customer education throughout that transition,” he says.

Nevertheless, most experts agree that moving to IPv6 is more a question of when rather than if, because at some point it will no longer be viable to stick with IPv4. Eventually, IT leaders will have to bite the bullet.

The IPv6 address space

Industry experts have been predicting the imminent exhaustion of the IPv4 address pool – which offers a maximum number of 4,294,967,296 static IP addresses – since the 1980s. But the dwindling pool of numbers has proved more capacious than first thought, thanks partly to network address translation methods.

With about 85 per cent of currently available IPv4 addresses already in use, and despite efforts to extend the pool further by freeing up previously reserved IPv4 addresses, some estimates suggest that the IPv4 address pool could be exhausted as early as 2010.

When the pool finally dries up, it will become difficult and expensive for organisations to obtain additional IPv4 addresses, which will add urgency to an IPv6 transition. This is why Viviane Reding, European commissioner for information society and media, wants a quarter of businesses to have adopted IPv6 by next year.