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Encyclopedia
Rotor machine
In cryptography, a rotor machine is an electro-mechanical device used for encrypting and decrypting secret messages. Rotor machines were the cryptographic state-of-the-art for a prominent period of history; they were in widespread use in the 1920s–1970s...
, the device used eight rotors each with a tyre ring and an insert. The machine was used mainly by the secret services from the late 1940s to the early 1950s.
