DNS (Domain Name System) always seems to be popping up when you want to create or modify a website. But if you’re not familiar with the concept, DNS can be a complicated issue to deal with. This article will explain the role of DNS on the web.
Imagine you posted a letter with the address ‘To Daniel’ written on the envelope. You would have an extremely small chance of that letter actually reaching the person named ‘Daniel’. Obviously this is because the post office would not have a unique address associated with the name ‘Daniel’.
The purpose of DNS is to associate a named address with a website address. We are used to seeing website addresses that we understand, like www.mydomain.com. But underneath the friendly human language lies a series of unfathomable numbers.
These numbers represent an IP address (IP refers to ‘Internet Protocol’). Every computer or device that is connected to the internet has a unique IP address. An IP address is made up of 4 sets of numbers separated with full stops between them, e.g. 126.96.36.199. IP addresses are used by network routers on the internet to send information between computers.
Essentially, a website address masks the IP address with a language that we can understand. So where does DNS come into all of this? The three components of a website address are separated by dots. The components are as follows:
- Hostname (www)
- Domain Name (mydomain)
- Top Level Domain (com)
When you register a domain name it is added to a root database. There is a root database for each Top Level Domain (TLD). When a name is added to this database it is associated with DNS servers that will hold the domain’s detailed information. This information tells computers where to send email and where to locate the websites. To resolve a domain name into a web address, a web browser must locate the domain’s DNS servers by querying the root database.
So if you change your domain information (‘Manage DNS’ on your 123-reg control panel) you are actually updating a database record. This record is called upon whenever someone types your domain name into their browser. The browser will ask the database for the IP address of where your domain lives, and then visit the server where your website resides. This allows the visitor to view a website or send an email.
DNS is a big subject, and can get quite complicated. There are many issues we could talk about. But for the meantime, I hope this post provides an effective overview of DNS and its purpose on the internet.