When 4 billion addresses aren't enough
[March 2011] Everybody has a name. We use names to help distinguish between members of a group: "Aroha said this", "Bob did that". But sometimes one name isn't enough. We might have to add a last name, hair colour, where someone comes from, or some other identifying characteristic to distinguish between two people with the same first name.
In the same way, every computer or other device needs its own unique "name" when it connects to the Internet so that the signals it sends and receives end up at the right place.
IP addresses
If you go to the web page What is my IP Address it shows you the unique address of your computer. That address will look something like 203.96.72.12.
Any individual digit in that sequence of four groups could be as small as 0 or as big as 255. That gives us around 4 billion possible combinations.
4 billion addresses aren't enough
In times gone by, 4 billion seemed like plenty of unique addresses. Now the world's population is more than 6 billion, and many people have several devices connected to the Internet.
Also, every printer, traffic light, mobile phone or whale tracker that connects to the Internet needs its own unique address.
That old system of creating Internet addresses was called IPv4. But now we've reached a very important moment: all the addresses have been allocated and we need more.
IPv6 addresses won't run out any time soon
There's a new system in town called IPv6, and it's time for us to switch. iPv6 allows for 340 undecillion addresses.
If you're like me, you've probably never heard of an 'undecillion'. Where a billion can be written as 10^9 (10 to the power of 9), an undecillion is 10^36. That's a lot of zeros and 340 undecillion addresses should hold us for a while.
The new IPv6 addresses will look more like this: 2001:0db8:85a3:0000:0000:8a2e:0370:7334
The above address shows 8 groups of numbers and letters separated by colons. The numbers and letters are in hexadecimal: any digit could be between 0 and f.
Aside: the decimal system we usually use counts from 0 to 9 — 10 numbers. The hexadecimal system doesn't stop at 9, but goes on to a, b, c, d, e and f, making 16 in all.
Unfortunately it's not as easy as just handing out new numbers. The underlying infrastructure has to change too, as there's actually a technical difference in the way things work.
What we need to do
You personally don't have to do anything, but the people who run the Internet do and your ISP has to as well. And by all accounts they need to get a move on.
You may find that sometime soon your ISP contacts you to talk about the IPv6 changeover. It's possible that you may need to change settings in your router or other equipment. The ISP should give you full details if that's required.
Read more
To read more about IPv4 and IPv6 try:
- Science Media Centre: Running out of IP addresses: the facts.
- Mashable: IPv4 & IPv6: A Short Guide.
Website tips contributed by Miraz Jordan, http://knowit.co.nz . Need help or advice about the Internet? Contact Miraz.
Miraz also writes the Tech Universe column for the NZ Herald - it's published online every weekday at http://bit.ly/bGX7UY .