DNS translates names to addresses in Intro to Computing - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

How DNS Resolves a Website Name

Imagine you want to visit a website by typing its name in your browser. Which step correctly describes how DNS helps your computer find the website's address?

A DNS creates a new website name for your computer to use.

B DNS stores the website's content and sends it directly to your browser.

C DNS blocks unknown website names to protect your computer.

D DNS converts the website name into an IP address so your computer can connect to the right server.

💡 Hint

Think about what your computer needs to connect to a website: a number called an IP address.

DNS stands for Domain Name System. It acts like a phone book that translates website names (like example.com) into IP addresses (like 192.0.2.1) so your computer knows where to go.

❓ trace

intermediate

Trace the DNS Lookup Process

Follow the steps below and choose the correct order in which DNS resolves a website name to an IP address.

A 1,2,4,3,5,6

B 1,3,2,4,5,6

C 1,2,3,4,5,6

D 1,2,3,5,4,6

💡 Hint

Think about the hierarchy from local to root to TLD to authoritative servers.

The DNS lookup starts at your computer, goes to the local resolver, then root servers, then TLD servers, then authoritative servers, and finally back to your computer with the IP address.

❓ identification

advanced

Identify the DNS Record Type

Which DNS record type is responsible for translating a domain name like example.com into an IPv4 address?

A CNAME record

B A record

C MX record

D TXT record

💡 Hint

Think about the record that holds the IP address for a domain.

An A record maps a domain name to an IPv4 address. MX records are for mail servers, CNAME for aliases, and TXT for text information.

❓ Comparison

advanced

Compare DNS and Hosts File

Which statement correctly compares DNS and the hosts file on a computer?

A DNS is a global system for name resolution; hosts file is a local file that can override DNS.

B DNS stores website content; hosts file stores IP addresses globally.

C Hosts file is used only for email; DNS is used only for websites.

D DNS and hosts file both store IP addresses but hosts file is faster because it is online.

💡 Hint

Think about where each system works: local computer vs internet-wide.

The hosts file is a local file on your computer that can map names to IP addresses and override DNS lookups. DNS is a distributed system used globally.

🚀 Application

expert

Diagnose a DNS Resolution Problem

You type a website name in your browser but get an error saying the site cannot be reached. You run a command to check DNS resolution and get no IP address returned. Which of the following is the most likely cause?

A The DNS server is down or unreachable.

B The website's server is turned off.

C Your browser cache is full.

D Your computer's screen resolution is too low.

💡 Hint

If DNS lookup fails, the problem is usually with the DNS server or network.

If DNS cannot return an IP address, it often means the DNS server is not responding or your computer cannot reach it. The website server being off would cause a different error after IP resolution.