The Phiastos Disc
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Chapter 8

CS 103 Cryptography

Making and Breaking the Code

        "Few persons can be made to believe that it is not quite an easy thing to invent a method of secret writing which shall baffle investigation. Yet it may be roundly asserted that human ingenuity cannot concoct a cipher which human ingenuity cannot resolve..."

        "It may be observed, generally, that in such investigations the analytic ability is very forcibly called into action; and for this reason, cryptographical solutions might with great propriety be introduced into academies as the means of giving tone to the most important of the powers of the mind."

        - Edgar Allan Poe, "A Few Words On Secret Writing": 1841.


Lesson 1 - History

Lesson 2 - RSA Cryptography

  1. To explore the history of cryptography.
  2. To be able to use several selected historical cipher systems.
  3. To understand the importance of data encryption in today's electronic world.
  4. To use a simplified RSA encryption example to decode a message given the public keys r and n.