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The Arizona STEM Acceleration Project

What is Cryptography?: Part 2

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What is Cryptography?- Part 2

A High School STEM lesson

Tabatha Hancock

May 2024

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Notes for teachers

This is part 2 of a two-part series. This lesson looks deeper into early electronic encryption tools and how they relate to cryptography today.

This lesson can be taught in a classroom setting or after-school club (such as a cybersecurity club).

This lesson can be simplified for middle school. It is not recommended for elementary school classes.

There is an optional extension that involves constructing an Enigma machine. There is a link to a kit, and the project requires students to solder. Students will need soldering experience before attempting this project.

If constructing an Enigma machine is not feasible, this lesson can be extended by allowing students to use this Enigma simulator. Use this bombe simulator to try to crack intercepted encrypted messages.

List of Materials

  • White copy paper
  • Markers
  • Poster board
  • Scissors
  • Glue/tape

Optional:

  • “Bombshell- The Hedy Lamarr Story�(Unrated. Preview with administration prior to use.)�
  • An Enigma kit or replica from Stegtronics. (https://www.stgeotronics.com/open-enigma)

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Standards

Technology

Standard 1. Empowered Learner

Standard 2. Digital Citizen

Standard 3. Knowledge Constructor

Standard 6. Creative Communicator�

English Language Arts (ELA)

Reading (Informational Text)

Writing

Speaking & Listening

Standards

Engineering

S2: Apply the Engineering Design Process

S5: Apply Technology to Engineering

S6: Apply Communications to Engineering

S7: Apply Project Management to Engineering

(These standards align with the optional Enigma replica/simulator activities)

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Objectives:

I will be able to explain the difference between encryption and cryptography.

I will investigate early electronic encryption tools.

I will present a brief history of an electronic encryption tool.

I will compare early encryption tools to the tools we use today.

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Agenda (Setting up our investigation)

What is “encryption”?� -Discuss the difference between cryptography and encryption.� -Highlight early electronic encryption tools.

Research Encryption Tools� -Separate into groups.� -Discuss group roles.� -Complete research requirements.� -Create a class presentation.

Class Presentation� -Groups present research assignments.

Hedy Lamarr- The Mother of Wi-Fi� -Present short video.� -Discuss the video and Lamarr’s impacts on our lives today.

Optional: A closer look at Enigma� -Construct an Enigma replica, and/or� -Use Enigma simulation to encode/decode messages between groups.� -Use Bombe simulator to try to crack coded Enigma messages.

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What is the difference between cryptography and encryption?

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What is the difference between cryptography and encryption?

Cryptography is the science of concealing messages with a secret code.

Cryptography is about studying methods to safely transmit information between parties.

Encryption is the act of concealing messages.

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Hands-on Activity Instructions

  • Discuss opening question.
    • Ensure students understand the difference between the difference between cryptography and encryption.
  • Share information about early electronic encryption devices and tools.
  • Break students into small groups.
    • Decide if you will assign research topics or allow students to choose their own
      • Students must have their topic approved by the teacher to prevent duplicated presentations.
    • To increase the number of research topics, you may choose to separate tools from their inventors.
    • Explain the task.
      • Consider having a printed list of objectives.
      • Research tool/inventor.
      • Construct a brief history.
        • Tools:
          • Why was it needed?
          • Who is credited as inventing it?
          • What effect did it have at the time?
          • Why is it important to cryptography today?
        • Inventors:
          • Brief history of their early life.
          • What was their contribution to cryptography?
          • Were they famous before this invention?
          • Were they known for any later inventions?

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Let’s look at four early electronic encryption tools

  • Hebern Rotor Machine
    • Edward Hebern�
  • Enigma Machine
    • Arthur Scherbius
  • Bombe
    • Edward Hebern�
  • The Colossus Computer
    • Arthur Scherbius

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Hebern Rotor Machine

Invented by Edward Hebern.

First cipher tool to use electrical circuitry.

First prototyped in 1917.

https://computerhistory.org/blog/before-enigma-breaking-the-hebern-rotor-machine/

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Enigma Machine

First patented in 1918 by Arthur Scherbius.

Used multiple rotor to scramble messages.

Continued to be developed by Scherbius until 1929.

https://www.dpma.de/docs/dpma/veroeffentlichungen/de536556a_chiffriermaschine1929.pdf

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Bombe

Created by Alan Turing and Gordon Welchman.

First Bombe (Victory) was used in 1936.

Used to crack Enigma encryptions during WWII.

https://www.tnmoc.org/bombe

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The Colossus Computer

Invented by Tommy Flowers in 1943.

First digital, programmable, and electronic computer.

Used to speed up Tunny code-cracking.

https://www.britannica.com/technology/Colossus-computerhttps://www.britannica.com/technology/Colossus-computer

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A deeper look

You will work in groups to research an electronic encryption tool.

  • About your tool:
  • About its creator:
  • Why was it needed?
  • Brief history of their early life.
  • Who is credited as inventing it?
  • What was their contribution to cryptography?
  • What effect did it have at the time?
  • Were they famous before this invention?
  • Why is it important to cryptography today?
  • Were they known for any later inventions?

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Share your findings

While groups are presenting, think about

  • What came next?

  • How did each tool contribute to the encryption technology we use today?

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Hedy Lamarr- The Mother of Wi-Fi

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Assessment

Informal assessments can be taken while monitoring group and class discussions. Use these observations to ensure students understand the basics of their research projects. Evaluate ability to communicate and work well within a group.

Presentations can be used as a graded summative.

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Differentiation

Use heterogeneous grouping to ensure small groups include a variety learning/leading styles.

If you know your students struggle with research projects, provide websites or printed articles for group projects.

Remediation

An Enigma machine replica kit can be purchased here. This replica can be created in a small group before or after this lesson. If it is to be used for a demonstration during this lesson, construction will need to be started several weeks in advance. The replica requires soldering skills and involves a large amount of small pieces to assemble.

A virtual Enigma machine can be found here. This can be used in lieu of or in conjunction with the physical Enigma replication.

Use either of these tools to assign encryption/decryption activities.

This bombe simulator can be used to try to crack “intercepted” messages between groups.

Extension/Enrichment

Actual student work mid-assembly

Actual student work mid-assembly

Actual student work mid-assembly