What is DNS and Why Do You Need It?

• Apr 03, 2017
• Architechs for the Web

If you're launching a business website, you will quickly learn that there are a lot of technical details behind even the simplest site. While your web developer will likely handle most of them, it's important for you to have some idea of what you need, what you are paying for, and how everything works. For example, DNS. While most of us have no real idea how DNS works or even what it is, the average person uses DNS multiple times per day. 

But what is it? In the simplest terms, the Domain Name System (DNS) is the Internet's version of an address book. The Domain Name System maintains a directory of domain names and translate them to Internet Protocol (IP) addresses for computers. 

Just like when you put an address into the GPS on your phone or in Google Maps, and the program automatically translates it to the correct latitude and longitude of your destination, DNS exists to tell computers where to go to find the content you're looking for.  DNS is primarily used to direct computers to the right websites from URLs, but is also used for web mail services. 

How Does DNS Work 

Domain Name System services allow you to sign a Uniform Resource Locator or URL to your website. This URL or web address is easy to remember for most users. For example, Architechsfortheweb.com is relatively simple to remember and allows us to easily inform anyone who wants to visit the site that they are visiting Architechs for the Web. But, machines still need the IP address. Using DNS also ensures that you can have more than one website on the same server. 

Visit any website, the browser checks its DNS cache to see if you've recently searched this before. If so, it will simply use this information. 

If you haven't recently searched this website, the computer contacts the closest site likely to have the information, typically the recursive DNS servers on your Internet Service Provider's servers, or the root Name Service Providers.

The computer provides an answer and directs you to the correct web address.

DNS and Email

Your email uses an address just like your website. Your email server uses a "Simple Mail Transfer Protocol" (SMTP) which checks the 'address' on your email and directs it where it needs to go. However, SMTP doesn't understand domain names, so it connects with the Domain Name System server. Just like with your web URL, the DNS translates your web address into an IP address. Then, it searches for an MX server (Mail Exchange server) on the IP, and organizes the mail on the server based on the name at the front of the email address, in this case, info.

Without DNS, your email client would have no idea of where to send the email. 

Setting up DNS Services

If you want your website to have a URL (and you do) or you want email, you need DNS. While there are some complexities to setting it up, your web developer can help you with the technical difficulties of changing your name servers 

Registering a Domain Name - Anyone can easily register their own domain name using a name registrar. Here, you can buy a web address or URL for a yearly fee. This fee pays for the domain name to be added to the registry of live websites, and pays for maintenance to ensure that people who type the URL into their web browser will come up with your website. 

Changing Name Servers - After you register your URL, you must update the DNS servers on your web host, so that the name servers point the URL at your website IP address. Then, when people type the URL in, your website comes up. The whole process takes 12-36 hours to complete, and is known as URL propagation. 

DNS services are an essential part of building a website. In addition to allowing your website to be found, they make it possible to brand your site, make it possible for search engines to index (store) and deliver your site in search, and enable everyone to visit your site. In short, if you want a website, you need DNS services.