The Crypto Challenge Contest
Four degrees of difficulty, from pen & paper to complex mathematical problems
Solved Level 1 challenge Number Sequence — Part 2
Solved Level 1 challenge From Russia with Love
Solved Level 1 challenge The Book Code: A Challenge for Bookworms
Solved Level 2 challenge Homophonic Encryption — Part 3
Solved Level 1 challenge Nils away on travel
Solved Level 2 challenge The Syllabary Cipher – Part 3
Solved Level 2 challenge Cracking SHA1-Hashed Passwords
Solved Level 1 challenge Original Caesar Cipher
Four degrees of difficulty, from pen & paper to complex mathematical problems