Don't panic, but be ready to adopt IPv6

Internet Protocol version 6 is an idea whose time has almost come. But what, if anything, should IT directors and network...

Internet Protocol version 6 is an idea whose time has almost come. But what, if anything, should IT directors and network managers be doing to prepare for it?

Internet Protocol version 6 is not that new. It has been around as an idea since the early 1990s and as a draft protocol since 1998. Now, though, it is starting to become something you might think about implementing in the next few years. But what is it, and when should IT departments take an interest?

Pros and cons

The most obvious advantage of IPv6 is that because it uses 128bit addresses instead of 32bit addresses, a lot more addresses are available - 34 x 1038 of them, instead of the theoretical maximum of 4.3 billion that exist in the current incarnation, IPv4.

Christian de Larrinaga, director of the UK IPv6 Task Force, says inefficiencies in IPv4 address management mean there are far fewer global addresses available than the theoretical total. Cisco estimates that two thirds of the available addresses will be used up by the end of this year.

IPv4 users work around shortages of addresses in various ways, for example by using network address translation, which allows more than one organisation to use the same address. However, there are disadvantages to these workarounds.

Address space conservation methods entail some reduction in application flexibility and user security, plus extra expense and complexity. Also, there can be problems with address conflicts, and large companies can face difficulty just managing their internal addressing structures.

Some technologies require, or work better with, fixed IP addresses. Always-on domestic internet connections and 3G mobile phone technology are among the developments that could steeply drive up demand for fixed addresses. With IPv6, it will theoretically be possible to give every device its own address, whether it be a car engine, the office coffee machine or a factory process control instrument.

Another advantage of IPv6 relates to its intrinsic end-to-end security. IPsec (IP Security) is built in to IPv6, whereas it is an "optional extra" in version four. Quality of service functions, the ability to multicast and Multi Protocol Label Switching (see glossary) are also built in to IPv6.

Given that IPv6 has been designed to solve the problems of IPv4, its only disadvantage should be the hassle and expense of transition. The process of migration will be helped by techniques that allow IPv4 and IPv6 to run on the same routers and over the same links. "Tunnelling" lets IPv6 traffic travel over an existing IPv4 infrastructure, so you can have islands of IPv6 in what is still essentially an IPv4 network.

Current status

Some pioneers are going through the pain of early adoption. Shinichiro Kashiwagi, manager of the Global IP Group at NTT Europe, says, "Japan has the second biggest amount of IP traffic in the world. The limited IPv4 address allocation for Japan was beginning to hinder new applications from emerging and that is why Japan had to be the earliest adopter of IPv6."

Other nations that are likely to get in early include Far Eastern countries that lost out when the IPv4 addresses were allocated and countries such as Afghanistan and African states that have never had much infrastructure.

Europe has its own pioneers. Jane Butler, regional head of strategy and collaboration at Cisco, chairs the 6Net consortium, set up two years ago by the European Commission. She says, "We now have a native testbed right across Europe, and many of the national research networks, including the UK Education & Research Networking Association, have deployed it."

When and why to deploy

For any company wanting to dip a toe in the IPv6 water now, there are testbeds. Major suppliers of networking equipment have been building it into their offerings and Microsoft is eagerly doing the same.

IPv6 services, too, are beginning to appear. This month, NTT Europe is launching a full commercial IPv6 service aimed at corporate users, ISPs and research establishments, corporate users and research centres.

Applications outside the enterprise could provide the initial impetus for IPv6 adoption. Peter Hovell, IPv6 team leader at BTexact Technologies, says, "Online gaming is going to be massive, and then there are the set-top boxes and VCRs that you would ideally like to be able to program remotely. With white goods such as washing machines, it would be useful for engineers to gain access remotely, particularly in countries where the equipment tends to be rented."

Businesses need not face a Y2K-style panic, since IPv4 and IPv6 can coexist. Nevertheless, some enterprises, such as those experiencing difficulty with address space, will want to start their move sooner rather than later.

"For companies operating globally it may make sense to migrate to IPv6 in countries that are early adopters," Butler says. "It is perfectly possible, for example, to run IPv6 in South America and IPv4 in the rest of the world, and doing that could offer a useful proving ground.

"Companies that have an extensive distribution of phones and personal digital assistants will also want to watch the technology especially closely."

Getting ready

For any organisation using IP networks, a smart move would be to ensure that both strategists and techies are keeping an eye on IPv6. "The point where it becomes cheaper to go to IPv6 than add another layer of bodges to IPv4 will vary from organisation to organisation," Hovell says.

"You need to be able to spot the right moment for yours, which will take a bit of hands-on technical experience as well as theoretical knowledge."

BTexact operates UK6x, an internet exchange for IPv6 that organisations can use to conduct pilot projects. Barclays Bank is one high-profile user of the service.

New purchases can also make it easier for your organisation to take advantage of IPv6 in the future. When procuring new network equipment, look for suppliers that already support IPv6 or have tangible plans to do so.

"That should not cost you more," says Hovell. "Where deploying IPv6 will cost more is in the areas of training and improvements to operational support systems, but those are often in need of improvement anyway."

As well as suppliers of network kit, it makes sense to quiz service providers and software suppliers, especially those producing operating software, about their plans for adopting IPv6.

The move to IPv6 is likely to take place gradually over the next few years - a five-year horizon is often mentioned - but with companies as influential as Microsoft beginning to push, it could be sooner. Being the first company with IPv6 is probably as pointless as being the first person with a videophone, but you will not want to be the last.

Larrinaga says, "Migration from IPv4 to IPv6 will require a large number of IPv4 addresses, exacerbating the IPv4 address shortage. And basic economics suggest that shortages put up prices." At that point, there could be something to be said for being ahead of the game.


  • Quality of service refers to the mechanisms in network software for prioritising different kinds of information - data, video, voice - into packets for sending over the internet

  • MPLS - Multi Protocol Label Switching is a standard for extra-efficient routing of packets over the internet using tags that contain forwarding information

  • Multicast is a method of transmitting information to more than one targeted recipient simultaneously.


  • Internet Protocol version 6 is the 128-bit successor to the existing 32-bit IPv4

  • IPv4 offers a maximum of approximately four billion IP addresses

  • IPv6 will provide a virtually limitless supply of device addresses

  • The continuing growth in the number of devices is driving the adoption of IPv6, particularly for companies doing business in regions where IPv4 is in short supply, such as the Far East and the developing world

  • Experts say UK enterprises have no pressing need to adopt IPv6 but they should keep an eye on developments so they are ready to move when the time comes.

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