DNS back to basics and a simple explanation

Before we start talking about DNS let try and get a bit of background information that will help us understand what DNS helps us do. But before we do that lets have a look at how computers talk to each other.

Almost all computers today are connected to a network. Whether that be a company network or a direct connection to the internet. All the wireless routers and network cables are there to help your computers talk to each other. To make this a little easier to understand think of your computer as a telephone. When you want to talk to your friend you need to know the phone number that will connect you to them. Computer work in a similar way, only problem is that the phone number is a little different. This phone number is called an IP address and the IP address for tekrevolution is 74.220.207.188. Now you may look at this and think that’s not too hard to remember. But if you are like me and spend a fair amount of time on the internet you could easily end up haveing to deal with hundreds of these IP addresses. Not impossible to remember but not too easy either. But as you know we don’t have to remember all these IP addresses and that’s thanks to DNS.

DNS or Domain Name System is a small program that runs on many servers around the world that converts the easy to remember names to the complicated IP addresses that computers use. Thanks to DNS when we type www.tekrevolution.com we get directed to the correct web server. Much like a phonebook works for calling your friends.

As you can imagine an address book that spans the entire glob might be a bit hard for one computer or one organisation to managing. so DNS has been designed on a upside down Tree format. At the top of the tree is what we call the root. The root is the beginning of the DSN system and has authority over all the domain names that come below it. The root is represented by a period in a DNS name. Another thing to remember is that a DNS name is read from right to left. so tekrevolution’s full domain name would be “www.tekrevolution.com.”. Thankfully the dot is automatically assumed so we don’t have to keep typing it in. Now if we keep reading to the left the next step in the tree is the .com. Left again and the next domain is tekrevolution and finally we get the www that is not a domain name but points to a computer in the tekrevolution domain. Each level in the domain is managed by a different computer and a different organisation. the root is managed by an organisation called the Internet Name Registration Authority. From there the .com .sa .uk and many more second level domains are managed by other organisations in different countries.

Hope you find this article interesting and I look forward to reading your comments and having a chat about DNS with you.

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