DNS root servers are responsible for taking you from A to B – they’re the literal ‘root’ of the Domain Name System (DNS), which is commonly regarded as the Yellow Pages of the internet.
In this post, we’ll help you understand what DNS root servers are and how they work to keep the digital world running smoothly.
- DNS root servers are the invisible backbone of web browsing that streamlines our navigation
- These root servers help navigate billions of web queries each day, condensing complex communication processes into a seamless internet experience
- Behind these root servers are 12 major organizations and other entities that help to manage and operate them
- And when root servers fail, the many individual physical servers around the world are there to save the day
What Is the Root Server of DNS?
The DNS Root Server is the first stage in the journey to getting to a webpage – from typing in the URL to the webpage loading onto your screen.
The 13 Root Servers are the core reference points for internet navigation, which are identified by letters A through M. Each of these clusters has multiple DNS root server locations spread around the world so the load can be shared, and there won’t be any failure points.
What is the DNS Root Zone?
To understand what the DNS Root Zone is, you can imagine a tree and think about its roots. The roots are the most integral part of the tree, and similarly, the DNS root zone is the highest-level directory in the DNS hierarchy.
This specific file has information about top-level domains (TLDs) like .com, .net, and .org, as well as country-specific TLDs like .ca for Canada and .uk for the United Kingdom.
How DNS Root Servers Work?
When you type in a URL, your computer doesn’t actually understand the alphabetic URL. Interestingly, your device uses DNS to translate it into a machine-friendly IP address.
It does so by sending a DNS query to something called a DNS resolver. If the resolver already recognizes the address from a previous query, the process is over. If not, it turns to the many Root Servers in the world for help.
The Root Server will first respond with the details of the TLD server, such as .com in a .com instance. After that, the TLD server brings the resolver to the DNS server hosting the domain’s data (example.com), receives the accurate IP address, and sends back the information.
The DNS resolver then passes that IP address to your browser, which is how you get the website data needed to display the site on your screen.
The process might sound like a long and complex process, but these interactions all happen within milliseconds.
Where Does the Root Zone Come From?
The Root Zone is created and maintained by an organization called the Internet Assigned Numbers Authority (IANA), a sector of the Internet Corporation for Assigned Names and Numbers (ICANN). They are responsible for coordinating important elements that keep the internet running smoothly.
How Do Resolvers Find DNS Root Servers?
As mentioned, resolvers need to find DNS Root Servers to begin the DNS lookup process. But how do they look for them?
The short answer is that they don’t have to.
Every DNS resolver has a list of the IP root server addresses built into its software (root hints file), so they can simply communicate with one of those IP addresses.
How Many Default Root DNS Servers Are There?
While there are only 13 main servers, there are multiple physical servers that work to replicate the main one through a technique called Anycast.
So, even though there might only be 13 unique servers, they’re distributed across thousands of individual physical servers around the world.
Scattering different DNS servers worldwide means the system is better equipped to withstand failures, attacks, or disruptions in one location without impacting the web’s overall performance. If one server goes down, traffic can easily be rerouted to another server.
It’s a bit like a city’s transportation network, where there isn’t just one way to get to your destination. Bus stations and subway stations are strategically spread out across various key locations, which helps prevent traffic and make sure transit is smooth and accessible. If one route goes down, there are still other ways to get to where you’re going.
Who Manages the DNS Root Servers?
There are 12 different organizations that manage each DNS Root Server letter, including:
- A – VeriSign Global Registry Services
- B – University of Southern California, Information Sciences Institute
- C – Cogent Communications
- D – University of Maryland
- E – NASA Ames Research Center
- F – Internet Systems Consortium, Inc.
- G – US Department of Defense Network Information Center
- H – US Army Research Lab
- I – Netnod
- J – Verisign Global Registry Services
- K – RIPE NCC
- L – ICANN
- M – WIDE Project
Who Maintains Root DNS Servers?
While the DNS Root Servers are managed by the 12 organizations listed above, maintaining and operating these servers also involves a few other entities, which include:
- VeriSign – You might have noticed that VeriSign manages two root servers (A and J), but they are also responsible for maintaining the root zone file, all while maintaining domain names and internet security.
- Internet Corporation for Assigned Names and Numbers (ICANN) – ICANN manages just one server (L) but has the big responsibility of coordinating the DNS root, IP addressing, and other internet protocol resources.
- Internet Assigned Numbers Authority (IANA) – A part of ICANN, IANA is responsible for maintaining and coordinating the DNS Root and root zone file.
- National Telecommunications and Information Administration (NTIA) – NTIA is an agency of the US Department of Commerce. They work with ICANN and VeriSign to validate changes to the root zone file before they are officially implemented.
DNS Root Servers List: What Are the 13 Root Servers and Where They Are Located
| Root Server | Operated By | Location |
| A | VeriSign | USA |
| B | University of Southern California, Information Sciences Institute | USA |
| C | Cogent Communications | USA |
| D | University of Maryland | USA |
| E | NASA (Ames Research Center) | USA |
| F | Internet Systems Consortium, Inc. | USA |
| G | US Department of Defense (NIC) | USA |
| H | US Army (Research Lab) | USA |
| I | Netnod | Sweden |
| J | Verisign, Inc. | USA |
| K | RIPE NCC | Netherlands |
| L | ICANN | USA |
| M | WIDE Project | Japan |
What Happens If a DNS Root Server Fails?
When a DNS Root Server fails, it initiates what’s known as a DNS failover. Right when a server goes down, the DNS server will redirect the DNS queries to an operational server through its built-in backup system.
During the process, the DNS resolvers request the IP address again, receive the updated address, and reroute the user.
Final Word: Harness the Power of DNS Root Servers
Understanding the mechanics of DNS root servers can prove to be invaluable in managing your digital presence. Whether you’re a seasoned webmaster or a beginner entrepreneur, don’t disregard the importance of DNS root servers, as they make up the foundation of internet navigation.
If you’re interested in learning more, check out our Next Steps and Learn More About DNS sections below!
Next Steps: What Now?
- Learn How to Manage DNS for Web Hosting
- Understand what a SOA Record is in DNS
- Check out the benefits of using a CNAME for DNS management
- Find the Best Web Hosting for your site
Learn More About DNS
- What Is a DNS? A Simple Guide to the Web’s Routing System
- What Is SOA Record in DNS? SOA Records Explained
- What Is SRV Record in DNS and How Does It Impact Your Website Hosting?
- What Is PTR Record in DNS? A Comprehensive Guide
- Guide to What Is TXT Record in DNS for Newbies
- What Type of DNS Record Is Used for Email Servers? A Introductory Guide
- What Is AAAA Record in DNS: Basic Guide to Web Navigation
- What Is a CNAME: A Thorough Introduction to DNS Management
- What Is Domain Propagation and How Does it Work?
- What Is an A Record? Exploring the Backbone of DNS
