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Demos

Pigpen Encoder


Click on Run Code or **See HTML in new window** to use the tool. ![](https://codehs.com/uploads/6d0a8975ba998f5303bd6ee510e61e76) <br> This tool encrypts a message using the Pigpen Cipher. Try a few messages and see if you can figure out how the encryption works.

Modulo Game!


Click on Run Code or **See HTML in new window** to play the game. ![](https://codehs.com/uploads/6d0a8975ba998f5303bd6ee510e61e76) <br> Read the directions and play the game! How challenging is it to guess the number? <br> Are there any "tricks" you can use? <br> **Advanced:** Choose the script.js file on the left and change the number 25 to a higher number for a more challenging game!

Diffie-Hellman Key Exchange


Click on **Open** to start the simulation. <img src="https://codehs.com/uploads/09165b1d9e4b5fc628049af9893bd821" width="450"> <br> This tool simulates how the Diffie-Hellman key exchange works. 1. Working with a partner, agree on a shared public color. 2. Then, hide the computer from your partner and choose a color for Aaron and for Beatriz. 3. Scroll down to view the shared secret color and write it down. 4. Scroll back up and remove the numbers from Aaron's secret color. 5. Knowing the public color, Beatriz's secret color and the shared secret color, can your partner determine Aaron's secret color? 6. Switch roles and try again!

Intranet Permissions


Click on Run Code or **See HTML in new window** to use the tool. ![](https://codehs.com/uploads/6d0a8975ba998f5303bd6ee510e61e76) <br> Company intranets have to be set up with the correct permissions to ensure that the user has the correct permissions based on their role or account. <br> This is an example how permissions might be set in a classroom or school intranet. Log in as student and try to access the answer key. What happens? <br> Log out and then log in as a teacher and try to access the answer key. <br> *Advanced*: Can you go into the script.js file and figure out how to adjust a student's permissions?