Symmetric encryption (AES, DES) in Computer Networks - Mini Project: Build & Apply

Understanding Symmetric Encryption with AES and DES

📖 Scenario: You are learning about how computers keep information secret when sending messages. Symmetric encryption is a way to lock and unlock messages using the same secret key. Two popular methods are AES and DES.Imagine you want to send a secret note to a friend. You both agree on a secret password (key). You use this key to lock your note so no one else can read it. Your friend uses the same key to unlock the note.

🎯 Goal: Build a simple explanation and example of symmetric encryption using AES and DES. You will create a list of encryption methods, set a secret key, show how to lock messages, and explain how the key is used to unlock them.

📋 What You'll Learn

Create a list called encryption_methods with the exact strings 'AES' and 'DES'

Create a variable called secret_key and set it to the string 'mysecretkey123'

Create a dictionary called encrypted_messages where keys are method names from encryption_methods and values are example encrypted texts

Add a final explanation string called explanation describing that the same secret_key is used to lock and unlock messages

💡 Why This Matters

🌍 Real World

Symmetric encryption is widely used to protect data in communication apps, online banking, and secure file storage.

💼 Career

Understanding symmetric encryption basics is essential for careers in cybersecurity, network administration, and software development focused on data security.

1

Create the list of encryption methods

Create a list called encryption_methods with the exact strings 'AES' and 'DES' in that order.

Computer Networks

# Create the list of encryption methods
encryption_methods = []
# Your code here

Need a hint?

Use square brackets to create a list with two strings: 'AES' and 'DES'.

2

Set the secret key

Create a variable called secret_key and set it to the string 'mysecretkey123'.

Computer Networks

encryption_methods = ['AES', 'DES']
# Create the secret key variable
secret_key = ''
# Your code here

Need a hint?

Assign the exact string 'mysecretkey123' to the variable secret_key.

3

Create encrypted messages dictionary

Create a dictionary called encrypted_messages where each key is a method from encryption_methods and each value is a simple example string showing encrypted text: 'Encrypted with AES' for AES and 'Encrypted with DES' for DES.

Computer Networks

encryption_methods = ['AES', 'DES']
secret_key = 'mysecretkey123'
# Create the encrypted_messages dictionary
encrypted_messages = {}
# Your code here

Need a hint?

Use curly braces to create a dictionary with keys 'AES' and 'DES' and their corresponding example encrypted strings.

4

Add explanation about symmetric key use

Create a string variable called explanation that says: 'Symmetric encryption uses the same secret key to lock and unlock messages.'

Computer Networks

encryption_methods = ['AES', 'DES']
secret_key = 'mysecretkey123'
encrypted_messages = {
    'AES': 'Encrypted with AES',
    'DES': 'Encrypted with DES'
}
# Add the explanation string
explanation = ''
# Your code here

Need a hint?

Assign the exact explanation sentence to the variable explanation.