IPv6: a technology sprint or a marathon?

While IPv4 addresses may never be completely exhausted they are, apparently, becoming scarce. According to the IPv6 Task Force, there are not enough IP addresses for every person on the planet today — let alone in 2050 when the world is expected to be home to some 9 billion people. That date may seem far away. But “whatever the economic constraints may be, we must clearly plan technically for all of these people to have the potential for Internet access,” the IPv6 Task Force concludes in its report
(www.ipv6-taskforce.org/PublicDocuments/Press_Release_on_IPv6_v6.pdf):

“It would not be acceptable to produce a technology that simply could not scale to be accessible by the whole human population, under appropriate economic conditions. Furthermore, pervasive use of networked devices will probably mean we will see many devices per person, not just one,” the report also states.

IPv6 is not a technology sprint, but a technology marathon Photo: OFTA (ITU 000077)

Imagine having an IPv6-based home appliance controller that enables you to feed your pet or to check if your home door is properly locked; all from a remote location! But this is no longer imagination. These intelligent appliances connected via an IPv6 network are well and truly being tested by companies such as NTT Communications (NTT Com).>

To quote the conclusions of the IPv6 Task Force: “That pressure is heightened because IP addresses are never fully utilized, either because allocations per Internet service provider or per site were too generous in the 1980s (some organizations have been allocated what amounts to 1/256th of the whole IPv4 address space), or because allocations have to be made in blocks of sizes that are multiples of two (computers being binary devices).” This implies that a site with 129 devices will have to be allocated 256 IP addresses.

Some engineers explain that the scarcity of the IPv4 address space has been masked by the use of a technique known as network address translation (NAT). NAT can be compared to PBX, which translates private addresses into global addresses when making external connections. Even when there is a large number of telephone units for extension, the necessary number of external lines is only the number sufficient for transferring simultaneous calls. NAT allows many networked devices to have their own local addresses, but they connect to the Internet through a device which holds a single IPv4 address.

So while a user (client) behind a NAT device can communicate out to servers on the Internet — the “client-server” communication model — that same user (client) cannot be guaranteed to be accessible when external devices wish to establish a connection. In this regard, the report of the IPv6 Task Force states that: “NAT breaks the end-to-end principle of the Internet, preventing the evolution of next generation applications that demand IP address space, and connectivity into business premises and home networks (e.g. from IP-enabled mobile handsets).”

It should be noted that some voices argue that the current IPv4 addresses space is adequate for the near future, especially if steps are taken to reclaim unused address blocks, and that the disadvantages of NAT can be overcome in many cases.

“The drivers in 1995 for the growth of the network are many. A few which I think are worth mentioning especially [include] the World Wide Web, which as you know emerged out of CERN, located here in Geneva. This has had a profound impact on the impression that people have of the Internet because it is now a medium with sound and imagery and motion — well beyond the kind of simple textual interfaces that we had when the system was first starting.” Vinton Cerf in a keynote address given at Internet@TELECOM 95 Photo: A. de Ferron (ITU 992411)

IPv6 has been in development since the early 1990s and is now said to have matured to the state where vendors such as Sun, Cisco, Ericsson Telebit, 6Wind, Hitachi, Microsoft, Nokia and Juniper are delivering early commercial products. Initial deployments are also being made.

“The value of IPv6 can be realized only if the deployment effort is broadly based on a global scale. Part of the IPv6 Task Force effort needs to be devoted to fostering IPv6 understanding where ever the Internet has gone, and beyond that to places where it can go with the help of the much-expanded IPv6 address space. I encourage your initiative and support your efforts to create a receptive environment for the development, delivery and use of IPv6 in the global Internet,” says Vinton Cerf.

Addressing the IPv6 Task Force, Mr Blois also remarked: “Initiatives like yours will guide decision-makers to implement on a national, regional and global basis the necessary concerted actions, which will make possible the goal of universal access to modern telecommunication services, particularly the Internet, paving the way towards an effective implementation of the Global Information Society.”

Latif Ladid, Chairman of the IPv6 Task Force and Vice-President of Ericsson Telebit says that: “Internet growth to a ubiquitous utility would require end-to-end address transparency and ease-of-use of IPv6 features and benefits to enable brand new peer-to-peer and secure applications such as 3G /IMT–2000, new Internet applications not imaginable 20 years ago.” He adds: “IPv6 is not a technology sprint, but a technology marathon. Everyone is called upon to make it happen.”