Cryptography came from Spartans Military (Greeks)
Kryptos means Hidden
Gráphō means writting
The diameter of the cylinder , therefore is the key
The scytale method was used by the government officials of Sprta to communicate with their military officer.
It was not until a couple of centuries later that another popular encryption method arises: The ceasar cipher, named after Julius Caesar.
Each Letter is replaced by only one cipher symbol
The problem so far for Cryptography
RSA Asymmetric Encryption
(Public key and Private Key)
Copy rights : All screenshots are taken from my own presentation that i did upon graduation.