We all use the internet in everyday life and are used to seeing names like google.com, facebook.com etc.   On the Internet, these are known as “domain names” and make the web easier to use.   Let’s face it, www.google.comis easier to remember than the “real” web address of “”.

Time for some technical background, so stick with me.  At least skip to the end for a great tip on how to protect yourself online!

The Internet was developed back in 1983 as a way to connect many computers together.    For this to work, each device needs to have a unique address.   Just like how every house has a unique street address, every computer has a unique internet address.    This means that data sent from one computer can be safely routed to another, just like how the postal service can route your mail.   This Internet address is known as an IP Address (or Internet Protocol Address).

Now there are two types of IP addresses, Private and Real.  Your router will have an “Real” address.    This address is allocated to your router by your provider (for example Bell) when it connects to the Internet.   Behind your router, any device that uses your home network is given an “Private” IP address.   You might have seen these, they’re usually of the form 192.168.0.x?

So why do we need Private and Real IP addresses?   Well every IP address is of the form x.x.x.x (where x can be any value from 1 to 255).   This gives a total of 4,294,967,296 addresses!   However, this just isn’t enough to cover all of the computers and devices out there.   So instead of giving every device in your home a precious real address, your router gives you a private address that isn’t actually unique.

Think of it like this..  An apartment building will have a unique “real address”.   Inside the building, each apartment may have a “private address” from 1-25?   If you want to send mail, you use both the real and private address to make sure it gets to the right destination.   All the mail may be delivered to the apartment building and then it’s down to the building manager to “route” the mail to the correct apartment.   This is what your router is doing – and why it’s called a router.

Internet routing is a complex and almost magical process.  The ability to route traffic between billions of devices without losing anything and all within a few milliseconds is pretty amazing!

So, everything has an IP Address, but we don’t tend to see them as Domain Names hide them from us to make the web easier to use.   Instead of having to remember a number to get to Google, you can type www.google.cominto your browser.   The translation between a name and an IP address is handled by something called a Domain Name Server (DNS).    You give it a name such as www.google.comand it tells your browser to go to address “”.

I promised you a tip on how you can use this to protect your computer.   There are now a few free services that can act as your DNS server to save you from reaching dangerous websites.   When you pass them a website to translate, they check it against a list of known “bad” websites first.   This means that every website is checked for you “before” you reach it.   This is much better than reaching a site and then having to block a virus from potentially infecting you.

There are two services I’d recommend for this purpose – OpenDNS and Norton ConnectSafe.   They both offer free versions of their service for home users.   By using this in conjunction with traditional anti-virus, you’re doubly protected from visiting dangerous websites.

If you’re interested in either of these services and would like a hand setting them up, drop me an email at [email protected].