How DNS Works

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How DNS Works?
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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?
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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.
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How Does DNS Work? DNS works collectively to
resolve the IP address for the domain name with
various DNS servers.
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1. If you type a domain name in the web browser and
   the system cant 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 cant 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 cant
   find it, and sends the query to the TLD.
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 cant find the IP
   address, the TLS redirects the resolvers to the
   Authoritative Name Servers.

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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.
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Final Words InfosecTrain is one of the best IT
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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

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