**Cipher disk** — The Union Cipher Disk from the American Civil War was 3.75 inches (95 mm) in diameter and made of light yellow heavy card stock. It consisted of two concentric disks of unequal size revolving on a central pivot. The disks were divided along their … Wikipedia

**Alberti cipher disk** — The Alberti cipher disk, also called formula, is a cipher disc which was described by Leon Battista Alberti in his treatise De Cifris of 1467. The device embodies the first example of polyalphabetic substitution with mixed alphabets and variable… … Wikipedia

**disk cipher** — noun cryptology : a cipher using the cipher disk … Useful english dictionary

**cipher wheel** — noun see cipher disk … Useful english dictionary

**Disk encryption theory** — Disk encryption is a special case of data at rest protection when the storage media is a sector addressable device (e.g., a hard disk). This article presents cryptographic aspects of the problem. For discussion of different software packages and… … Wikipedia

**Disk encryption software** — To protect confidentiality of the data stored on a computer disk a computer security technique called disk encryption is used. This article discusses software that is used to implement the technique (for cryptographic aspects of the problem see… … Wikipedia

**cipher** — cipherable, adj. cipherer, n. /suy feuhr/, n. 1. zero. 2. any of the Arabic numerals or figures. 3. Arabic numerical notation collectively. 4. something of no value or importance. 5. a person of no influence; nonentity. 6. a secret method of… … Universalium

**Alberti cipher** — The Alberti Cipher was one of the first polyalphabetic ciphers. Leon Battista Alberti Created in the 15th century (1466/67) by Leon Battista Alberti, it was the peak of cryptography at that time.Its inventor was Leon Battista Alberti, an… … Wikipedia

**Polyalphabetic cipher** — A polyalphabetic cipher is any cipher based on substitution, using multiple substitution alphabets. The Vigenère cipher is probably the best known example of a polyalphabetic cipher, though it is a simplified special case. The Enigma machine is… … Wikipedia

**Combined Cipher Machine** — CSP 1600, the replacement stepping unit to adapt the ECM Mark II to CCM The Combined Cipher Machine (CCM) (or Combined Cypher Machine) was a common cipher machine system for securing Allied communications during World War II and for a few years… … Wikipedia