How DNS Works
                     How DNS Works?
www.infosectrain.com | [email protected]
Like humans communicate with each other, computers also do communicate with 
each other, but not by the names; they have their unique numbers, such as IP 
addresses over a network. Humans are customized to address by the names 
instead of numbers to identify a person or a site. To communicate between 
computers and humans, networking engineers developed a Domain Name Server 
(DNS). This blog is curated about how DNS works. But before that, What is DNS?
www.infosectrain.com | [email protected]
What is DNS?
Domain Name Server (DNS) is a system that includes a database of the public IP 
addresses with website names. It acts as a resolver that converts domain names to IP 
addresses. If a user wants to open Google on the chrome page, DNS will resolve the 
name Google and check for the IP address in the cache memory. Based on the IP 
address, the computer gets connected with the web server and retrieves the web 
page to perform various actions on the Google web page.
How Does DNS Work?
DNS works collectively to resolve the IP address for the domain name with various 
DNS servers.
1. If you type a domain name in the web browser and the system can’t find the IP 
address in its cache memory, it will redirect the query to the Resolver server.
2. The Resolver server is an Internet Service Provider (ISP); it checks for the IP 
address in its cache memory. If it can’t find the IP address, it will further redirect 
the query to the root server.
3. The Root server is the top server of the DNS hierarchy, including 13 sets of root 
servers around the world. Each set of the root servers has its unique IP address. 
When the root server receives the query for the IP address but can’t find it, and 
sends the query to the TLD.
www.infosectrain.com | [email protected]
4.   The TLD server is the Top-level Domain Server that stores various address 
information for the domains such as .net, .com, .en, .org, and more. When the 
query is received but can’t find the IP address, the TLS redirects the resolvers to 
the Authoritative Name Servers.
www.infosectrain.com | [email protected]
5.   The Authoritative Name Server is responsible for knowing everything about 
Domain, including the IP address. When the query is received from the DNS 
resolver, the authoritative name server should respond to the server with the 
IP address.
6. And the DNS resolver will communicate with the system to retrieve the web 
page.
Once the DNS resolver receives an IP address from various servers, it stores the 
IP address in its cache memory. In case, if the computer sends the same query 
for the same domain name, it can retrieve the IP address from memory and 
mitigates the whole DNS Server process in the search for the IP address.
Final Words
InfosecTrain is one of the best IT Training and consulting platforms that offers an 
instructor-led training program on various IT security and cybersecurity domains. 
It provides the Network Security Training course by the well-experienced and 
certified trainers to cover a wide range of Networking concepts. To know more 
details, check out and enroll now.
www.infosectrain.com | [email protected]
About InfosecTrain
• Established in 2016, we are one of the finest 
Security and Technology Training and 
Consulting company
• Wide range of professional training programs, 
certifications & consulting services in the IT 
and Cyber Security domain
• High-quality technical services, certifications 
or customized training programs curated with 
professionals of over 15 years of combined 
experience in the domain
www.infosectrain.com | [email protected]
Our Endorsements
www.infosectrain.com | [email protected]
Why InfosecTrain Global Learning Partners
Certified and Flexible modes Access to the 
Experienced Instructors of Training recorded 
sessions
Post training Tailor Made 
completion Training
www.infosectrain.com | [email protected]
Our Trusted Clients
www.infosectrain.com | [email protected]

Contact us
Get your workforce reskilled 
by our certified and 
experienced instructors!
IND: 1800-843-7890 (Toll Free) / US: +1 657-722-
11127  / UK : +44 7451 208413
[email protected]
www.infosectrain.com