Have you ever wondered what a “fully qualified domain name” is? You may have heard it in passing, but not really understood the meaning. Well, today I want to shed some light on this topic and provide an explanation of just what a fully qualified domain name entails.
A FQDN consists of two parts: the hostname and the domain name. The hostname identifies which computer or device you are trying to reach, while the domain name provides information about where that specific device is located.
The hostname is the name of the specific computer or device on the network. The domain name is the name of the larger network to which the computer belongs.
So for example, if your laptop’s IP address were 123.456.789 then its FQDN would be my-laptop-123456.com (assuming my-laptop-123456 was registered as the hostname). Got it? Good!
Now that we have a basic understanding of what a FQDN is, let’s take a look at how they are used. In most cases, you will use your FQDN when you need to access something on the internet. This could be anything from logging in to your email account to visiting your favorite website.
There are two main ways that you can go about doing this: manually typing in the full address or using what’s known as a “DNS shortcut”. The first option is pretty self-explanatory; just enter the complete domain name into your web browser’s address bar and hit enter. The second option is a little more complicated but can be very useful if you frequently visit a site that has an FQDN with more than three or four components.
When you type a website address into your web browser, your computer uses its hostname to find and connect to that website’s server. The domain name part of the address helps route traffic to the correct server.
Your computer’s hostname can be anything you want it to be, but it must be unique on your local network. The domain name must also be registered and assigned to a specific IP address. If you own a website, your web hosting company will provide you with both a hostname and a domain name for your site.
You can also use a domain name to create an email address. Just add “@” and the domain name to the end of your hostname. For example, if your hostname is “mysite.com“, you could create an email address like “[email protected]”.
When you type in a website URL or email address, your computer looks up the corresponding hostname and domain name in a DNS (Domain Name System) server. The DNS server keeps track of all registered domains and their corresponding IP addresses. If your computer can’t find the information it needs in its local DNS server, it will query other servers until it finds what it’s looking for.
That’s a quick overview of FQDNs!