Where the theory meets the code.

The project in one paragraph#

The core demonstration shows how two participants establish a shared secret key using Diffie–Hellman in Java. Neither private key is ever transmitted. Both sides derive the same key from public values, then use it to encrypt and decrypt a message.

Project purpose#

This project was designed to:

1. Apply modular arithmetic and discrete logarithm concepts in a practical setting.
2. Implement Diffie–Hellman key exchange with clear parameter handling.
3. Show how a shared secret can support encryption and decryption.
4. Reinforce core public-key cryptography principles through reproducible examples.

Learning objectives#

• Apply discrete mathematics concepts used in public-key cryptography.
• Implement Diffie–Hellman key exchange in Java.
• Verify that both participants derive the same shared secret.
• Use the shared secret for encryption and decryption flow validation.
• Document architecture, code behavior, and test evidence in a reproducible format.