Fill device
Overview
Key (cryptography)
In cryptography, a key is a piece of information that determines the functional output of a cryptographic algorithm or cipher. Without a key, the algorithm would produce no useful result. In encryption, a key specifies the particular transformation of plaintext into ciphertext, or vice versa...
into electronic encryption
Encryption
In cryptography, encryption is the process of transforming information using an algorithm to make it unreadable to anyone except those possessing special knowledge, usually referred to as a key. The result of the process is encrypted information...
machines. Fill devices are usually hand held and battery operated.
Older mechanical encryption systems, such as rotor machine
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...
s, were keyed by setting the positions of wheels and plugs from a printed keying list. Electronic systems required some way to load the necessary cryptovariable data. In the 1950s and 1960s, systems such as the U.S.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
National Security Agency
National Security Agency
The National Security Agency/Central Security Service is a cryptologic intelligence agency of the United States Department of Defense responsible for the collection and analysis of foreign communications and foreign signals intelligence, as well as protecting U.S...
KW-26
KW-26
The TSEC/KW-26, code named ROMULUS, was an encryption system used by the U.S. Government and, later, by NATO countries. It was developed in the 1950s by the National Security Agency to secure fixed teleprinter circuits that operated 24 hours a day...
and the Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
's Fialka
Fialka
In cryptography, Fialka is the name of a Cold War-era Soviet cipher machine. A rotor machine, the device uses 10 rotors, each with 30 contacts along with mechanical pins to control stepping. It also makes use of a punched card mechanism. "Fialka" means "violet" in Russian...
used punched card
Punched card
A punched card, punch card, IBM card, or Hollerith card is a piece of stiff paper that contains digital information represented by the presence or absence of holes in predefined positions...
s for this purpose.
