DNS, or Domain Name System, is an internet protocol that acts as a bridge between human-friendly, easy-to-remember domain names and computer-readable IP addresses. It uses a well-structured system to efficiently match domain names with the right IP addresses, simplifying communication between users and computers.
- DNS helps users access websites using human-readable names instead of long, easy-to-forget IP addresses
- Multiple DNS servers find the authoritative nameserver that knows the IP address needed to access the website
- The root nameserver, TLD nameserver, authoritative nameserver, and DNS resolver help with the DNS lookup process to find the correct IP address of the website you want to visit
- You can stay cyber-safe by being aware of the risks, investing in malware protection, and switching to a secure DNS server
What Is a DNS?
The Domain Name System (DNS) serves as the internet’s phonebook. It’s a fundamental part of the internet that pairs domain names with their corresponding IP addresses. This makes browsing simpler, as users can easily remember human-readable domain names instead of long, complex IP addresses.
When you enter a domain name, like hostadvice.com, DNS servers translate it into an IP address that browsers can understand. This process allows for seamless communication between devices connected to the internet.
Why Is DNS Important?
DNS plays a vital role in making the internet more accessible to all. It allows users to access the websites they want quickly and efficiently, without having to memorize long strings of numbers. In short, DNS makes the internet user-friendly.
DNS also allows businesses to make changes to their web services without disrupting their online presence. For example, they can switch to a new web host without affecting their web traffic simply by updating their DNS records. Without DNS, businesses and organizations would have to start from scratch every time they make a change.
Origins of DNS: From ARPANET to DNS Invention
Back in the day, the U.S. Department of Defense‘s ARPANET relied on a massive digital “phone book” to connect research centers. But as the network expanded in the 1970s, managing computers and their lengthy numerical IP addresses became a real headache, leading to the need for a unified system.
That’s when Paul Mockapetris and Jon Postel, two American computer scientists, stepped in and created the Domain Name System (DNS) in 1983. This invention quickly became an Internet Standard, streamlining how applications communicate with end users.
How DNS Works: Breaking It Down
DNS is vital in the modern internet landscape. To put it in perspective, over 350.5 million domain names were registered by the end of Q1 2023. Without DNS, navigating this vast digital landscape would be a daunting, near-impossible task.
Resolving domain names can involve several steps and interactions with multiple DNS servers. Let’s dive into how DNS works:
1. Entering a URL
The DNS process kicks off as soon as you type a website’s URL into your browser and hit enter when you’re surfing the web. The DNS then figures out the website’s IP address so you don’t have to remember a bunch of numbers.
2. Querying the Recursive Resolver
Your browser shoots a request to a DNS recursive resolver, which is usually given to you by your internet provider. This resolver checks if it already has the IP address you’re looking for in its cache.
3. Asking the Root Nameserver
If the resolver doesn’t know the IP address, it asks a root nameserver for some help. The root nameserver then points the resolver to the Top-Level Domain (TLD) nameserver.
4. Contacting the TLD Nameserver
The resolver gets in touch with the TLD nameserver, which knows a bit about the second-level domain (like hostadvice.com). The TLD nameserver tells the resolver where to find the authoritative nameserver for the domain.
5. Reaching the Authoritative Nameserver
The authoritative nameserver knows the IP address you need. It gives the IP address to the recursive resolver.
6. IP Address Sent to Browser
The resolver sends the IP address back to your browser, which then connects to the web server hosting the website using that IP address.
7. Webpage Loads
Finally, the web server sends the requested webpage to your browser. Your browser then connects to the IP address and loads the website for you. This entire process takes just a few seconds, allowing you to access websites quickly and easily.
Which DNS Servers Are Used to Load Websites?
When your computer can’t find an IP address for a website in your cache or host’s file, it turns to four DNS servers to help it out. Let’s go over each one of these servers to see how they work together.
3. DNS Resolver
The DNS resolver, also called the recursive resolver, is the first to engage in the DNS lookup process. It’s like a middleman between your computer and other DNS servers.
The resolver’s main job is to find the correct IP address for the website you want to visit. If the resolver already has the IP address stored in its cache, the request ends there, and you can immediately access the site. However, it will send the request to the root nameserver if the resolver can’t find the IP address in its cache.
2. Root Nameserver
The root nameserver is the first step in translating domain names into IP addresses. It doesn’t store the IP addresses you’re looking for, but it points you in the right direction. It identifies the top-level domain when a recursive resolver sends a request, tells it where to go next, and helps you get to the right IP address for the website you want to visit.
Think of the root nameserver as a reference desk in a library. It points to different sections where you can find the book you’re looking for.
3. TLD Nameserver
The TLD nameserver hosts the last portion of the hostname, such as “com” in hostadvice.com. This helps narrow down the search for the correct IP address. It’s similar to a specific rack of books within a particular section of the library.
4. Authoritative Nameserver
The authoritative nameserver is the final destination for your DNS request. It holds all the information about the domain name you want to visit, including its IP address. It’s like a dictionary on a specific rack in the library.
Important: When working with DNS and making changes, exercise caution and avoid any unplanned alterations. This is especially important when it comes to the authoritative nameserver, which has all the information about a specific domain.
What Are the Types of DNS Queries?
There are three types of DNS queries, which help speed up the resolution process and improve your online experience. These include:
1. Recursive Query
A recursive query asks the DNS server to find the IP address of a specific domain name. The server returns the IP address if it’s cached. Otherwise, it starts a recursive query process until the authoritative name server with the information is found. The information is finally sent back to the DNS resolver and your computer, allowing you to access the website.
Recursive queries are essential for translating domain names into IP addresses and letting users access websites on the internet. They ensure that the DNS resolver will provide an answer to the client and can locate the relevant IP address, even if it has to search through multiple DNS servers to find it.
2. Non-Recursive Query
A non-recursive query involves asking the DNS server for a record it already has. This is faster than a recursive query because the server can immediately return the DNS record without asking other DNS servers. DNS servers often store records to improve performance.
Non-recursive queries make DNS resolution faster by skipping extra steps. They’re useful when the DNS server has the necessary information in its cache, which cuts down the number of queries and lightens the load on DNS infrastructure.
3. Iterative Query
The DNS resolver gives the best answer it can to the client’s question. If it has the needed records cached, it responds right away. If not, it points the client to the closest authoritative name server in charge of the needed DNS zone. The client asks the referred server, and this cycle goes on until a useful DNS record or an error comes up.
In simpler terms, an iterative query is like playing a game of “20 Questions” with the DNS resolver. The client asks, and the resolver gives its best answer. If it’s unsure, it offers a hint for the client to refine their question. This goes on until the client gets the needed answer. It’s helpful for digging up specific info about a domain name or IP address.
What Is DNS Security, and Why Is It Important?
It’s surprising, but the backbone of internet connectivity, DNS, wasn’t built with cybersecurity as a top priority. It’s tough to block or monitor DNS in a business setting, which leaves it open to hackers to carry out DNS abuse. Last year, the DNS attack’s impact on business loss and brand damage actually went up. This is where DNS security comes in.
DNS security is all about keeping the DNS infrastructure safe from cyber attacks, ensuring it stays fast and reliable. A solid DNS security plan uses multiple defenses, such as backup DNS servers, security protocols like DNSSEC, and thorough DNS logging to keep things secure and running smoothly.
A DNS simplifies your browsing experience by turning easy-to-read website names into IP addresses computers understand. Understanding what a DNS is can let you navigate the online world more efficiently and bolster your internet security.
Plus, if you’re in business and rely on web hosting or email hosting for your daily operations, knowing how DNS works can help you stay ahead in today’s digital landscape. Implementing strong DNS security measures allows you to protect your online presence, maintain customer trust, and ensure the smooth functioning of your daily operations.
Next Steps: What Now?
- Learn How to Manage DNS for Web Hosting
- See the Top 5 Website Builder Providers
- Check the Top Web Hosting Providers