DNS (Domain Name System) in Computer Networks - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does DNS stand for and what is its primary purpose?

DNS stands for Domain Name System. Its primary purpose is to translate human-friendly website names (like www.example.com) into IP addresses that computers use to find each other on the internet.

beginner

What is an IP address in the context of DNS?

An IP address is a unique number assigned to each device on the internet. DNS converts website names into these numbers so computers can communicate.

beginner

What is a DNS server?

A DNS server is a computer that stores a directory of domain names and their corresponding IP addresses. It answers requests from your device to find the IP address for a website name.

intermediate

What happens if a DNS server cannot find the IP address for a domain name?

If a DNS server cannot find the IP address, it will ask other DNS servers or return an error saying the website cannot be found.

beginner

Why is DNS important for everyday internet use?

DNS is important because it makes the internet easy to use. Instead of remembering complex numbers (IP addresses), people can use simple names to visit websites.

What does DNS translate?

A Emails to phone numbers

B IP addresses to website names

C Passwords to usernames

D Website names to IP addresses

DNS translates website names (like www.google.com) into IP addresses so computers can locate websites.

Which device typically asks a DNS server for an IP address?

A A television

B A printer

C Your computer or smartphone

D A router only

Your computer or smartphone sends a request to a DNS server to find the IP address of a website.

What is the role of a DNS server?

A Store and provide IP addresses for domain names

B Store passwords for websites

C Send emails

D Control internet speed

DNS servers store domain names and their IP addresses and provide this information when requested.

If DNS did not exist, what would users need to do to visit websites?

A Use email addresses

B Remember and type IP addresses

C Use phone numbers

D Use social media handles

Without DNS, users would have to remember the numeric IP addresses of websites, which is difficult.

What happens when a DNS server cannot find a domain name?

A It returns an error or asks other DNS servers

B It redirects to a random website

C It shuts down

D It sends an email to the user

If a DNS server cannot find the IP address, it either asks other DNS servers or returns an error message.

Explain how DNS helps you visit a website using a simple example.

Think about what happens when you type a website name in your browser.

Describe what would be difficult about using the internet if DNS did not exist.

Consider how you use website names now versus numbers.