The best way to begin understanding cryptanalysis is to try your own hand at code breaking — Good Luck!
TRY OUT ONE OF THE LINKS BELOW:
- Combo-Code Hacking: Substitutions and Transpositions
- Hacking: Substitution – Caesar – Vigenere
- Competition CODE BUILDING — use this page to submit all competition codes!
- Competition Code HACKING CHALLENGES
Math Circle Cryptography
- Hacking with an Oracle (Cipher Oracle, by Mike H.)
- Code Design Challenge (Code Builder, by Zandra V.)
- Code Design Sandbox (Code Builder with unlimited $, by Zandra V.)
MORE CRYPTANALYSIS MATERIALS: An introduction to many practical code building and hacking techniques, and a quick review of historically memorable codes. (Including presentations and handouts)