The Crypto Challenge Contest
Four degrees of difficulty, from pen & paper to complex mathematical problems
Solved Level 1 challenge Letter to the Templars — Part 1
Solved Level 1 challenge A disguised code
Solved Level 2 challenge Not-so-Secret Message from Malawi — Part I (RSA)
Solved Level 1 challenge Grille Cipher
Solved Level 2 challenge Broadcasting and low exponent — RSA Attack
Solved Level 1 challenge Number Sequence — Part 3
Solved Level 1 challenge Number Sequence — Part 2
Solved Level 1 challenge Original Caesar Cipher
Four degrees of difficulty, from pen & paper to complex mathematical problems