Some interactive demos of simple symmetric key substitution cyphers:
- Pigpen Cypher
- Caesar Cypher
- Vignère Cypher
Text can be enetered into either the plaintext or cyphertext inputs, keys adjusted, etc. The encryption system is shown and updates as text is typed.
Also shown is a letter frequency chart to help show how each scheme would be susceptible / resist a frequency analysis attack.
Demos of modern symmetric and asymmetric (public-key) crypto.
The demo show the key distribution, and how this can be problematic for symmetric key schemes, where an eavesdropper can compromise the system. But then shows how this issue is solved in the case of public-key, asymmetric crypto.