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Texas Foundations of Cybersecurity

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The ABCs of Cryptography
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
Description

In this lesson, students will learn and use hashing functions. They will look at what hashing is, requirements of a good hashing algorithm, how hashing is used, what the ideal hash function does, collisions in hashing, and how hackers try to crack a hashing algorithm.

Objective

Students will be able to:

  • Identify what a hashing algorithm is and its related vocabulary, such as digest and collisions
  • Describe what makes an ideal hashing algorithm and why they are important in encryption and cybersecurity overall
  • Describe how malicious actors try to crack hashing algorithms
Description

In this lesson, students look at hash function development by delving into modulo math. Modulo math is very important in advanced cryptography since it’s a one-way function where the output hides the input very well. This makes it useful in creating hashing functions.

Objective

Students will be able to:

  • Solve simple modulo problems
  • Explain why modulo math is useful in hashing algorithms and protecting data in cybersecurity
Description

In this lesson, students will learn about SSL certificates: what they are, where they come from, how they work, and why they are essential to internet security.

Objective

Students will be able to:

  • Explain the role of SSL certificates in internet security
  • Explain how certificates work, including how to obtain one, their relationship with public and private keys, and how the chain of trust is used to create trust additional checks of authenticity
  • Explain how stapling and pinning strengthen the security of a certificate

1.9 The ABCs of Cryptography Quiz