DNS poisoning in Computer Networks - Mini Project: Build & Apply

Understanding DNS Poisoning

📖 Scenario: You are learning about how the internet translates website names into IP addresses using the Domain Name System (DNS). Sometimes, attackers try to trick this system by changing the address information, which is called DNS poisoning.In this project, you will build a simple example to understand how DNS poisoning works by creating a small DNS table, setting a trusted domain, simulating an attack, and then fixing the table.

🎯 Goal: Build a simple DNS table and simulate a DNS poisoning attack by changing the IP address of a trusted domain. Then, restore the correct IP address to understand how DNS poisoning can be detected and fixed.

📋 What You'll Learn

Create a dictionary representing a DNS table with domain names and their IP addresses

Add a variable to store the trusted domain name

Simulate DNS poisoning by changing the IP address of the trusted domain

Restore the correct IP address to complete the DNS table

💡 Why This Matters

🌍 Real World

DNS poisoning is a real threat that can redirect users to fake websites, causing security risks like data theft or malware infection.

💼 Career

Understanding DNS poisoning helps network administrators and cybersecurity professionals protect internet users by detecting and preventing such attacks.

1

Create the DNS table

Create a dictionary called dns_table with these exact entries: 'example.com': '93.184.216.34', 'openai.com': '104.18.30.162', and 'testsite.com': '192.0.2.1'.

Computer Networks

# Create the dns_table dictionary with domain names and IP addresses
# Your code here

Need a hint?

Use curly braces {} to create a dictionary with keys as domain names and values as IP addresses.

2

Set the trusted domain

Create a variable called trusted_domain and set it to the string 'example.com'.

Computer Networks

dns_table = {
    'example.com': '93.184.216.34',
    'openai.com': '104.18.30.162',
    'testsite.com': '192.0.2.1'
}
# Create the trusted_domain variable and set it to 'example.com'
# Your code here

Need a hint?

Assign the string 'example.com' to the variable trusted_domain.

3

Simulate DNS poisoning attack

Change the IP address of the domain stored in trusted_domain inside dns_table to '123.45.67.89' to simulate DNS poisoning.

Computer Networks

dns_table = {
    'example.com': '93.184.216.34',
    'openai.com': '104.18.30.162',
    'testsite.com': '192.0.2.1'
}
trusted_domain = 'example.com'
# Change the IP address of the trusted_domain to '123.45.67.89' to simulate poisoning
# Your code here

Need a hint?

Use the variable trusted_domain as the key to update the IP address in dns_table.

4

Restore the correct IP address

Change the IP address of the domain stored in trusted_domain inside dns_table back to the original IP '93.184.216.34' to fix the DNS poisoning.

Computer Networks

dns_table = {
    'example.com': '93.184.216.34',
    'openai.com': '104.18.30.162',
    'testsite.com': '192.0.2.1'
}
trusted_domain = 'example.com'
dns_table[trusted_domain] = '123.45.67.89'
# Restore the IP address of trusted_domain to '93.184.216.34'
# Your code here

Need a hint?

Assign the original IP address back to the key stored in trusted_domain in dns_table.