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.
• How Does DNS Work?
• DNS works collectively to resolve the IP address
  for the domain name with various DNS servers.
• 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.
• 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.
• 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.

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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.
• 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
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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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