We are at the dawn of the age of IPv6, the Internet protocol that will succeed version 4. With 340 undecillion available addresses, IPv6 ensures that the Internet can continue growing and offers advantages in terms of stability, flexibility, and simplicity in network administration.
The Internet is a communications network formed by millions of interconnected computers that share data and resources. All the computers on the network use the Internet protocol (IP) so that users can read a web page or send an e-mail and be sure that information is properly sent and received. The protocol assigns a numeric code (IP address) to each device on the network in order to identify it. In other words, “the IP protocol is the universal language that allows all the devices connected to the Internet to understand each other,” says Xavier Hesselbach, a member of the research group on Design and Evaluation of Broadband Networks and Services.
IPv4, the first commercial version of the Internet protocol, is still widely used. It was created in the early 1980s under the direction of the Internet Engineering Task Force (IETF), the organisation in charge of developing and promoting new technological standards for use on the Internet. When IPv4 was initially deployed, the Internet consisted of a relatively small number of computers, used mainly by universities and the military. As a result, it was possible to introduce version 4 of the protocol in a single day, 1 January 1983, known as Flag Day. At the time, no one could imagine reaching the current 4 billion addresses. But with the passage of time the situation has changed completely. According to data published in 2011 by Internet World Stats, over the last decade the number of users connected to the network went from 300 million to almost 2 billion. Using a PC or laptop to access the Internet from home, or connecting via a smartphone or tablet is no longer anything out of the ordinary. And these are no longer the only devices hooked up to the Internet. Sensors that measure temperature, humidity, or a patient’s vital signs, and smart tags that provide information on the origin of a product and update its price are among the devices that require an IP address to form part of the network.
As we have connected more and more devices to the Internet, the number of IP addresses available under version 4 of the protocol has diminished at a spectacular rate and they are now running out, even though in many cases various devices share the same address using a mechanism known as network address translation (NAT). On 3 February 2011, the Internet Assigned Numbers Authority (IANA), the organisation that oversees global IP address allocation, assigned the last block of addresses (33 million) to the Asia Pacific Network Information Centre (APNIC), one of five regional Internet registries, which is responsible for managing addresses for Asia, Australia and New Zealand.
The problem of IPv4 address exhaustion was first raised in 1990. The IETF recognised that there were not enough addresses to meet projected demand and that they would eventually run out. At that point, work began to develop the next version of the protocol for sending and receiving data over the Internet: version 6 or IPv6.
A business opportunity
Version 6 of the Internet protocol supports a mind-boggling 340 billion billion billion billion (340 undecillion) addresses. This solves the problem of IPv4 address exhaustion; addresses no longer need to be shared, and the problems this gives rise to are avoided. There are more than enough IPv6 addresses to assign one to every computer, mobile phone, refrigerator, washing machine, car, or power point we may wish to connect to the Internet, and this connectivity makes it possible to communicate directly with these devices.
“Such a substantial number of addresses could facilitate the deployment of what has been called the Internet of Things, a network in which objects as well as users are identified,” says Anna Calveras, a researcher with the Wireless Networks Group. “All the devices you can imagine could have their own networks and communicate with each other,” she concludes.
This technology has countless applications. At the moment, “the focus is on applications in the context of the home, building control, smart cities, and industry,” says Carles Gómez, who also works with the Wireless Networks Group. “Behind this development, there’s a whole industry promoting the standardisation of mechanisms for using IPv6 in these environments. A lot of people are realising that this technology represents a business opportunity,” he adds.
IPv6 has other advantages. One aspect of the protocol that the UPC scientific community is enthusiastic about is its autoconfiguration mechanism. Any device connected to the network automatically obtains a unique IP address and other parameters needed to communicate. No human intervention is required in this process. This mechanism is particularly useful when a large number of devices need to be connected to the network, as in the case of the Internet of Things.
According to Jordi Casademont, another researcher with the Wireless Networks Group, an additional advantage is that “IPv6 is designed to strengthen security and increase communications quality of service.” IPv6 also makes information easier to process, an improvement that affects devices though it has no direct impact on users. According to Rafael Vidal, the researcher who coordinates the Wireless Networks Group, “one of the problems with Internet networks is that links have become very fast, but the elements through which information passes have to do so much work that in the end these elements, known as routers, can become a communication bottleneck. With version 6 of the protocol, it’s possible to do more with the same router capacity. As a result, there aren’t so many congestion problems and information can be transmitted more smoothly.”
Adapting to the protocol
Although IPv6 is an approved standard, it is being deployed at a very slow rate. For over ten years, the research community has been insisting on the need to make the transition, and many have noted that despite its availability the technology is not being widely used. One reason for this is that IPv4 and IPv6 are not compatible, which makes the transition much more complicated. Experts do not foresee any problems with the use of the Internet in the immediate future, but address exhaustion could lead to complications in some areas.
The need is most acute in countries like China, where the number of Internet users is increasing exponentially, and other Asian and African countries that have been assigned a very limited number of IP addresses.
Clearly if the transition does not take place, the Internet will not be able to grow, and there will come a day when it is no longer possible to connect new users and devices. It may even become impossible for current IPv4 users to connect to those with IPv6 addresses. But deployment is not a simple issue to resolve, and everything appears to indicate that it will not happen in a harmonised way. The various Internet actors (service providers, makers of hardware, operating systems, applications, etc) may know what their own plans are for the transition to IPv6, but at present there is no global plan.