Complete · Technology · Security
Basic cryptography
Three short lessons in how encryption works, from the Caesar and Vigenère ciphers to the Diffie-Hellman key exchange that lets two strangers agree on a secret over an open line.
- 01 Basic cryptography – the Caesar cipher One of the most basic encryption schemes is the Caesar cipher. It's weak in practice, but a great way to learn how crypto works. Jan 28, 2022
- 02 Basic cryptography – the Vigenere cipher The Vigenere cipher is more complicated that the Caesar cipher but based on the same idea. It uses a running key to keep your message secure. Jan 30, 2022
- 03 Basic cryptography – Diffie-Hellman key exchange How do you communicate securely over an insecure medium? Using the Diffie-Hellman key exchange to agree on an encryption key is a start! Feb 3, 2022
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