Future of Internet Backbone

Update

Since writing this article others have also been writing about the same issue, here are two good articles which shed more light on this issue.

Welcome to my students starting the Cisco IT Essentials course in Alice Springs and Darwin. In this blog I want to talk about the problem with the backbone of the Internet and what is happening to fix it.

The Internet works using a protocol called IP (Internet Protocol) which is transmitted through the phone and telecommunications system using a protocol called TCP (Transmission Control Protocol). The whole thing is wrapped up in the term TCP/IP which this tutorial from W3Schools explains really well.

Every server on the Internet has an IP address and you need one to access the internet. Whoever gives you access (school, University or ISP) gives you an IP address when you log onto their system. This IP address can be used to track your movements and activities while on the Internet. This website will show you your IP address and tries to work out where in the world you are.

This system has worked really well since it was first established in the early 1980s. However it faces a problem today, we are running out of IP addresses. When this happens (see clock) no new servers will be able to connect to the Internet.

The version of IP (called IPv4) that we use currently uses 4 sets of 32bit numbers (like 192.168.0.0), which means we have 2 to the power of 32 or 4,294,967,296 addresses available. (actually less than that because some are reserved for other things) A newer version of IP called IPv6 uses uses 128 bit octets (like 2001:0db8:85a3:08d3:1319:8a2e:0370:7334), which means that we have 2 to the power of 128 or (rounded version sorry none of my programs could calculate the actual number) 300,000,000,000,000,000,000,000,000,000,000,000,000 possible addresses. To put this in perspective, if every person on earth used a billion addresses each, there would still be plenty left over.

So how long before IPv6 is ready to use? To change over all the parts of the internet must be able to use IPv6, browsers, operating systems, physical equipment, logical control systems, supporting software etc. Most of this is in place now, here is a list of current sites that can only be accessed if you are using IPv6, see whether you can see them.

The browsers and operating systems have been ready since 2000, switching gear has also been made compatible and some small systems have already made the change. So anything build or bought in the last 10 years should be right, but there is an great deal of infrastructure on the internet that is older than that. Australia is ahead of the pack in getting ready for this. There is a conference later on this year to discuss this very issue. The issue for the ISPs is not when to switch, but how to enable both to the run side by side. The browsers have no difficulty with this but other control aspects do have a number of technical and control issues. All the various protocols of TCP/IP (see the tutorial earlier) must be able to work with information in both formats. Cisco has been working on this for 10 years so many of the issues have been solved in the lab and now need to be tested in the field. Internode already has started trialling an implementation while the other major ISPs are working on this as well.

I would suggest that what will probably happen is that the ISPs will gradually switch over to IPv6 but still maintain IPv4. This means that your browser will use the most appropriate IP version during a transition stage and both will run side by side for a while. One day when you check your IP address it will be a strange new number, rather than the familiar one. You probably won't notice any other difference. For the average user this change will not be noticeable, it will just be a huge headache for those trying to administer the system.