What is a DNS server? How Do Domain Name System Servers Connect You to the Internet? A DNS server helps your web browser connect to websites. A DNS server, short for Domain Name System server, converts web addresses to IP addresses. Without a DNS server, you will not be able to connect to any website. If you’re having trouble with your default DNS server, you can change it.
What is the DNS server?
A Domain Name System (DNS) server is a key part of the Internet’s backbone – without it, it would be impossible to use a web browser to find websites. You can think of the DNS server as a phone book. When you ask your computer to load a website, the DNS server matches the name of the website with the IP address. This allows your computer to find it and charge it correctly.
When you write a URL, you are actually telling your computer to find and connect to another IP address. To do this, it uses a series of associated servers, which all form the DNS server. Here is how it works.
The DNS process, step by step
- Ask your web browser to load a website. Since computers do not speak English, your browser cannot read a name such as “www.guidesmartphone.net” and needs an IP address instead. For this reason, please send your request to a recursive DNS resolver. The purpose of recursive DNS resolver is to find the IP address connected to the website you entered.
- The first step of the resolver is to find the “Top Level Domain” or “TLD” of the website, in other words, whether it is a .com, .net, .org or another. type of site. He does this by asking to the root nameserver, which maintains a list of all websites in each TLD.
- Once the resolver knows the TLD, it switches to the TLD name server correspondent (for example, the .com name server) and asks it to find the correct IP address.
- The TLD name server finds the IP address and passes it to the authoritative nameservers, who will find out if this address is correct.
- The authoritative name server sends a message to the address and waits for a response – if it gets the correct response, it has the correct IP address for the desired website.
- If the IP address is correct, the authoritative name server sends it back to the web browser.
- Once the web browser receives the correct IP address, the web page begins to load.
This all happens in seconds – if your internet connection is very fast, or if you have recently visited the site (see below for more information), it can happen in milliseconds.
Caching can avoid calling DNS server
If you visit a new website, your browser will go through the entire process described above. But if he did this for every website, things might slow down – that’s why recently visited websites are cached in the web browser.
When you try to load a website, the DNS server first checks your fileto see if the IP address is already registered there. If so, it will retrieve the IP address directly from the cache, which saves time.
Each entry in the cache has an associated time limit, called time-to-live (TTL). The TTL for any IP address is usually around 48 hours, and once that has passed, the IP address will disappear from the cache. This means that the DNS server will have to start the whole recursive search process again.
Read our article if you want to know: how to make a DNS change.
Typically, the web browser uses a standard public DNS server, which is typically configured and maintained by the Internet service provider. However, some advanced users manually change their DNS server. It can increase internet speed and protect your privacy.
Changing the DNS can be done through the “Network” menu of the computer in the Settings application. If you are looking for a new DNS, you can try Google’s DNS server or any number of other custom DNS servers.