Cryptography | M-94

M-94

The M-94 was a cryptographic cipher device, which was used by United States Army consisting 25 aluminium discs, arranged in a cylindrical shape on an axle. Each alphabet letter disc had scrambled. Message was encrypting by using turning discs until all plain texts was arranged in a one line. And another line of disc was then read off and sent as a cipher text. In the order of the different discs was the actual secret key. Although the M-94 provided a low level of security it was good enough for tactical purposes. It remained in service until 1943.