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Fundamentals of Cybersecurity (2020)

Description

In this lesson, students will learn how basic encryption and decryption works. There is a need for secrecy when sending and receiving personal information. Encryption and decryption are used to protect personal information.

Objective

Students will be able to:

  • Define cryptography, cryptology, and cryptanalysis
  • Explain the need for encryption and how basic encryption and decryption works
  • Relate encryption with how it affects the CIA Triad
Description

In this lesson, students will learn the history of cryptography. Humans have always had reasons to hide information, and throughout history they have used crypto systems of varying complexity to keep information safe.

Objective

Students will be able to:

  • Explain the purpose of cryptography and how different crypto systems have been used throughout history
Description

In this lesson, students will learn and practice using the Caesar Cipher. The Caesar Cipher is an encryption method that predates computers in which each letter of the message is shifted by a certain amount, called the key.

Objective

Students will be able to:

  • Encrypt and decrypt messages using the Caesar Cipher
Description

In this lesson, students will practice using brute force and letter frequency to crack the Caesar Cipher. The Caesar Cipher is an encryption method in which each letter of the message is shifted by a certain amount, called the key. Cracking the Caesar Cipher with brute force (trying every combination) is a trivial matter for modern computers.

Objective

Students will be able to:

  • Explain why the Caesar Cipher is so easy for a computer to crack
  • Use basic letter distribution analysis to decrypt a simple message
Description

In this lesson, students will learn and use the Vigenère Cipher. The Vigenère Cipher consists of several Caesar ciphers in sequence with different shift values based on a keyword, so brute force and letter frequency analysis do not work.

Objective

Students will be able to:

  • Explain how the Vigenère Cipher works and why it is not as easy to crack as the Caesar Cipher