You’ve probably read in the press that the Internet is almost ‘full’. Just as we can run out of phone numbers in a particular area, and have to add another digit, we can run out of IP addresses—the Internet equivalent. Rather than add one digit, though, we are quadrupling the size of the address. This would be a nuisance if you actually had to type the addresses, but usually you don’t. They are used by your computer, behind the scenes, but you don’t see them.
When telephone numbers are changed, there is usually a transitional period where both work. The same is true now, on the Internet. The original addresses, called IPv4 (‘Internet Protocol version 4’) still work. People are beginning to support the new addresses, called IPv6. A few sites can only be reached using IPv6, like this one.
If you get any Internet services from me, you can use them over IPv4 or IPv6. That will not change until it becomes difficult to buy IPv4 service, probably in a few years time. From my logs, I know how many people’s computers are connecting using IPv6 when they have a choice. Essentially it is not happening, which is rather alarming when you consider that the remaining IPv4 addresses will probably be gone this year.
To see how alarming it really is, we need to do one more test. If a site supports IPv4 and IPv6, it isn’t a disaster if your computer chooses to access it using IPv4. What happens, though, if the site only supports IPv6? It would be helpful for me if you could click this link, using as many different computers as you can. The link takes you to a test site which only supports IPv6. Either post a comment or email me to tell me what happens. If it seems to be a dead link, your computer has no support at all for IPv6. Alternatively, you may see a page which gives some information about the IPv6 connection your browser has set up, as well as the IPv6 address that you used. In that case, it would be helpful to know what the IPv6 address was.
If you see a dead link, don’t panic. ISPs will have to do something about IPv6 for their customers. I suspect they are panicking. No one quite knows how IPv6 will be provided to broadband users. We do know two very inconvenient things: (i) it will have to be done soon because IPv4 addresses are running out, and (ii) your broadband router probably doesn’t support IPv6 in the way your ISP would find most useful.