ciphertext letter

См. также в других словарях:

• cryptology — cryptologist, n. cryptologic /krip tl oj ik/, cryptological, adj. /krip tol euh jee/, n. 1. cryptography. 2. the science and study of cryptanalysis and cryptography. [1635 45; < NL cryptologia. See CRYPTO , LOGY] * * * Introduction …   Universalium

• Vigenère cipher — The Vigenère cipher is a method of encrypting alphabetic text by using a series of different Caesar ciphers based on the letters of a keyword. It is a simple form of polyalphabetic substitution.The Vigenère (pronEng|ˌviːdʒɪˈnɛəɹ, veedj ih nair )… …   Wikipedia

• Four-square cipher — The Four square cipher is a manual symmetric encryption technique. It was invented by famous French cryptographer Felix Delastelle.The technique encrypts pairs of letters ( digraphs ), and thus falls into a category of ciphers known as… …   Wikipedia

• M-209 — can also refer to a highway in the U.S. state of Michigan; see M 209 (Michigan highway) In cryptography, the M 209, designated CSP 1500 by the Navy (C 38 by the manufacturer) is a portable, mechanical cipher machine used by the US military… …   Wikipedia

• Frequency analysis — In cryptanalysis, frequency analysis is the study of the frequency of letters or groups of letters in a ciphertext. The method is used as an aid to breaking classical ciphers.this is wrong is based on the fact that, in any given stretch of… …   Wikipedia

• Jefferson disk — The Jefferson disk, or wheel cypher as Jefferson named it, is a cipher system using 26 wheels, each with the letters of the alphabet arranged randomly around them. First invented by Thomas Jefferson in 1795, it did not become well known and was… …   Wikipedia

• Autokey cipher — An autokey cipher (also known as the autoclave cipher) is a cipher which incorporates the message (the plaintext) into the key. There are two forms of autokey cipher: key autokey and text autokey ciphers. A key autokey cipher uses previous… …   Wikipedia

• Smithy code — This article refers to a cipher used in 2006 by Mr Justice Peter Smith and inserted into his judgment in the litigation concerning alleged plagiarism by Dan Brown. For the prisoner code invented by Capt. Smitty Harris in 1965, see Tap Code. The… …   Wikipedia

• 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 brief but prominent period of history; they were in widespread use… …   Wikipedia

• DRYAD — This article is about the enciphering system. For other uses, see Dryad (disambiguation). The DRYAD Numeral Cipher/Authentication System (KTC 1400 D) is a simple, paper cryptographic system currently in use by the U.S. military for authentication …   Wikipedia

• Chaocipher — The Chaocipher [1] is a cipher method invented by J. F. Byrne in 1918 and described in his 1953 autobiographical Silent Years[2]. He believed Chaocipher was simple, yet unbreakable. Byrne stated that the machine he used to encipher his messages… …   Wikipedia