This project uses an Enigma machine simulator. It functions like the Enigma machines used during World War II. This example has been included to help you better understand how encryption worked in the early days. It’s a great learning tool when you first start exploring the subject of cryptography. Enigma machines provided fairly good encryption strength for their day. Modern cryptographic systems are much more secure than Enigma machines. Pay attention to the colored paths as you type. The red path goes through the three rotors, bounces off the reflector, becomes green, and then goes back through the three rotors. The right rotor moves with each keystroke. If it completes one full cycle, it will advance the middle rotor and subsequently the left rotor.
1. Open a web browser and go to http://enigmaco.de/ enigma/enigma.swf.
2. Use the left and right arrows to move each of the top three rotors so that each has the letter “A” selected in blue.
3. Click in the Input text box in the bottom of your screen.
4. Slowly type your first name and last name without a space. (In this case it was RandyBoyle. If you make a typing error you can start over by pressing the backspace key.)
5. Take a screenshot. Note: The text in the Input text box is what you typed. The text in the Output text box is what you would send. You are now going to reset the dials to their original position (in this case AAA) and type the encrypted text (ciphertext) you produced in the Output text box. You can copy the ciphertext from the screenshot you just took. Subsequently, you should see your name reproduced in the bottom box. This is the equivalent of decrypting the message.
6. Click in the Input text box and backspace your name. (The rotors should be set back to their AAA position.)
7. Refer back to the screenshot you just took and copy down the output (ciphertext). (In this case, the ciphertext for “RANDYBOYLE” was “VDOLZYMEAC.”)
8. Type the ciphertext into the Input text box. (Type slowly so you won’t make a mistake and have to start over!)
9. Take a screenshot with your name showing in the Output text box.
10. Backspace the text in the Input text box.
11. Slowly press the A key ten times and notice how a different encrypted letter is chosen as output through the rotating dials even though you are hitting the same key each time.
12. Take a screenshot.