Unicity distance — is a term used in cryptography referring to the length of an original ciphertext needed to break the cipher by reducing the number of possible spurious keys to zero in a brute force attack. That is, after trying every possible key, there should… … Wikipedia
Unicity (disambiguation) — Unicity refers to various things.As a city zoning and city unification term, Unicity may refer to: * An section of the city of Winnepeg, Manitoba * The unification of the City of Cape Town s local government * The 1971 City of Winnipeg Act, which … Wikipedia
Information theory — Not to be confused with Information science. Information theory is a branch of applied mathematics and electrical engineering involving the quantification of information. Information theory was developed by Claude E. Shannon to find fundamental… … Wikipedia
Nihilist cipher — In the history of cryptography, the Nihilist cipher is a manually operated symmetric encryption cipher originally used by Russian Nihilists in the 1880s to organize terrorism against the czarist regime. The term is sometimes extended to several… … Wikipedia
One-time pad — Excerpt from a one time pad In cryptography, the one time pad (OTP) is a type of encryption, which has been proven to be impossible to crack if used correctly. Each bit or character from the plaintext is encrypted by a modular addition with a bit … Wikipedia
Substitution cipher — In cryptography, a substitution cipher is a method of encryption by which units of plaintext are replaced with ciphertext according to a regular system; the units may be single letters (the most common), pairs of letters, triplets of letters,… … Wikipedia
Caesar cipher — The action of a Caesar cipher is to replace each plaintext letter with one fixed number of places down the alphabet. This example is with a shift of three, so that a B in the p … Wikipedia
Brute force attack — In cryptanalysis, a brute force attack is a method of defeating a cryptographic scheme by trying a large number of possibilities; for example, possible keys in order to decrypt a message. In most schemes, the theoretical possibility of a brute… … Wikipedia
List of physics topics R-Z — NOTOC A B C D E F G H I J K L M N O P Q R S T U V W X Y Z … Wikipedia
Topics in cryptography — This article is intended to be an analytic glossary , or alternatively, an organized collection of annotated pointers.Classical ciphers*Autokey cipher *Permutation cipher*Polyalphabetic substitution **Vigenère cipher*Polygraphic substitution… … Wikipedia
Ciphertext-only attack — In cryptography, a ciphertext only attack (COA) or known ciphertext attack is an attack model for cryptanalysis where the attacker is assumed to have access only to a set of ciphertexts. The attack is completely successful if the corresponding… … Wikipedia
