Here’s a quick quiz: which do you find easier to remember, the number or the name:
I’d wager most people choose
google.com. It’s pretty hard for us humans to work with and remember numbers. We much prefer to remember names.
A short memory test
Here you are — just remember this number till the end of this article:
Domain names and IP addresses
Did you know that you can type either
google.com into your web browser’s Address Bar, and both take you to the same web page?
In the real world an address may look like this:
123 High Street, Anytown, New Zealand.
In the Internet world addresses look like this:
220.127.116.11. That’s what known as a ‘dotted quad’ IP address. IP stands for ‘Internet Protocol’.
Directories remember for us
In the real world a friend may recommend a lawyer or accountant by name. We then locate them by consulting a phone directory. The directory tells us that Bigge, Learge and Caustly can be found at 1 Bank Street — it matches up the name with a specific address.
Websites work the same way.
When we type in a domain name such as
google.com our computer has to figure out the address to visit to fetch the information we require.
Domain Name Servers
There are directories on the Internet that hold big lists of domain names and the actual address where each domain name can be found.
When you type a domain name such as
google.com into your web browser’s Address Bar your computer actually consults a Domain Name System (DNS) server.
The computer asks for the address that matches
google.com and the DNS Server replies with
Then your computer sends the appropriate signals off to the appropriate places and before you know it the Google Search engine shows up on your screen.
Spot the weakness
That’s all a whole lot of theory, and I’ve skipped over some nitty gritty details that real networking experts would feel are very important. I think it explains the general process though.
But have you spotted the weakness in all of this?
Picture this scene from an old movie: the car chase is on. The good guys are after the villains. The villains in the lead turn right at the signpost. But before they turn they jump out and turn the signpost round so it points the wrong way. The good guys read the sign and turn left.
In a future tip I’ll talk about what happens if the Domain Name Server points the wrong way.
BTW: the web is big, very big
In July 2008 the Official Google Blog wrote in We knew the web was big…:
Recently, even our search engineers stopped in awe about just how big the web is these days — when our systems that process links on the web to find new content hit a milestone: 1 trillion (as in 1,000,000,000,000) unique URLs on the web at once!
What was that number again? Did you remember
18.104.22.168? Type it into your web browser’s Address Bar, and it should take you straight to the much more memorable
Written by Miraz Jordan for, and reproduced from CommunityNet Aotearoa Panui, June 2009. This article has been modified for publication here.