Internet access has become a critical service for the public sector and commercial businesses; the Internet economy is worth £100bn in the UK alone, contributing to over 7% of GDP1. Over time we have come to expect a certain level of performance and user experience from business Internet. We also take it for granted that we will be able to reach everyone, and everyone will be able to reach us.

In terms of deploying new Internet infrastructure it has been ‘business as usual’ for over three decades. But now it’s time for a long-anticipated, underlying logical upgrade to deal with Internet growth. This change will have a global impact on every organisation with an Internet connection, eventually affecting the configuration and operation of every Internet device in the world, from routers, firewalls and servers, to PCs, laptops and smartphones.

IPv4 addresses are running out – how will the Internet keep growing?

Internet Protocol version 4 was designed to provide 4.3 billion IP addresses – back in 1977 this seemed like more than enough for the experimental research networks of the time. However, by the early 1990s, it became apparent that the Internet would become something much bigger. It was obvious many more IPs would be needed and simply trying to conserve addresses, either through allocation or mechanisms such as NAT, was not going to be sustainable indefinitely.

The current annual rate of Internet growth, in terms of IP usage, is about 8%. Globally we are consuming around 200 million IP addresses each year. In January 2011 ICANN allocated the final “blocks” of address space to the various Regional Internet Registries, including RIPE. The RIRs themselves are expected to make their own final allocations before the end of 2011. After this, each ISP will allocate their remaining stock of IPs.

Internet Protocol version 6 was developed to deal with the exhaustion of IPv4. Version 5 was previously assigned to another experimental protocol which was never publicly used. There are a number of differences between IPv4 and IPv6, but the most important is the huge increase in available address space.

The length of an IPv6 address is 128 bits, compared to 32 bits in IPv4, so we have 2128 (340 undecillion) possible addresses. But what does that mean? Well, the earth is about 4.5 billion years old. If we had been assigning IPv6 addresses at a rate of 1 billion per second since the earth was formed, we would have by now used up less than one trillionth of the address space.

Why is IPv6 such an important issue for the public sector?

PSNGB understands the strategic importance of IPv6 and is helping the public sector prepare for the future. We know that Internet access is critical, meaning a failure or degraded level of service can have a serious impact on the following:

  • Workforce productivity
  • Core business activities
  • Ability to compete
  • Public facing services
  • Business continuity

The annual demand for 200 million addresses is not going to stop; adoption of IPv6 is the only way the Internet can sustain this growth. There is no “plan b”. It is important to note that there is no reliable method of translation between IPv4 and IPv6, because the complexity of DNS and application-layer issues are too great to deliver an acceptable level of service.

Why can’t we just translate between the old and new Internet? Think about human resources in the business. When staffing a UK office, it would not be possible for a non-English speaker to operate effectively through a translation device. Too much would be lost in translation. You would need them to speak English – be multilingual – to be productive in the role. The issue of translation between IPv4 and IPv6 is similar.

When IPv4 has run out, businesses can no longer make the assumption that the entire Internet will be reachable, or that they themselves will be universally reachable. Everyone must take steps to prepare their network for “both Internets”.

Those of us who build and support networks need to learn new protocols and new practices. This includes all ISPs and their customers. These changes will impact all network segments, from the Internet backbone right into the business LAN environment and end-user devices.

Unfortunately no public sector organisation can isolate itself or hide from these issues: the Internet is a network, so there are inherent network effects which mean that the actions of others directly affect our own. Regardless of our own plans for IP consumption as a business, we can be assured that the rest of the world will keep adding users, content and services. Eventually these new end points will only be available via IPv6. Therefore we must all act to ensure compatibility in the future.

1 U.K. Internet Economy Report (

%d bloggers like this: