The mechanics of the Double Playfair are involved enough that it is expected that solving this cipher would be most readily achieved by a computer program that recovers the first square by shifting ...

The Playfair cipher is an incredibLe code system that is both difficult to decrypt without a computer and easily solvable by hand. You might be familiar with the Cryptoquip in the comics section of a ...

This cipher is quite difficult with the amount of information available here. Wartime cryptanalysts expected to be able to solve for the keywords after 150 to 200 plaintext-ciphertext pairs were ...