Category

Classical ciphers

page 1

simple and widely known encryption technique

Vigenère cipher

simple type of polyalphabetic encryption system

right|frameless

substitution cipher

method of encoding by which units of plaintext are replaced with ciphertext, according to a fixed system; the "units" may be single letters (the most common), pairs of letters, triplets of letters, mixtures of the above, and so forth

secret language game

thumb|right|A scytale with a leather strip

thumb|The Hebrew alphabet, run through Atbash. Atbash (; also transliterated Atbaš) is a monoalphabetic substitution cipher originally used to encrypt the Hebrew alphabet. It can be modified for use with any known writing system with a standard collating order.

Playfair cipher

early block substitution cipher

transposition cipher

method of encryption by which the positions held by units of plaintext (which are commonly characters or groups of characters) are shifted according to a regular system, so that the ciphertext constitutes a permutation of the plaintext

Polybius square

type of cipher used in World War I

square table of alphabets

type of substitution cipher

substitution cipher based on linear algebra

Āryabhaṭa numeration

Alpha-syllabic numeral system

polyalphabetic cipher

term in cryptography

type of substitution cipher

historical encrypted manuscript

steganography method

encoding for text messages

classical cipher

a type of cipher that was used historically but now has fallen, for the most part, into disuse. In contrast to modern cryptographic algorithms, most classical ciphers can be practically computed and solved by hand

French cypher that remained unbroken for several centuries

Nihilist cipher

manually operated symmetric encryption cipher

class of ciphers

four-square cipher

symmetric encryption cipher

Encryption and decryption method

rail fence cipher

type of transposition cipher

type of cipher in cryptography

cipher used by Soviet spy Reino Häyhänen

Alphabetum Kaldeorum

Cipher created in 1467 by Leon Battista Alberti

Beaufort cipher

polyalphabetic encryption system

The DRYAD Numeral Cipher/Authentication System (KTC 1400 D) is a simple, paper cryptographic system employed by the U.S. military for authentication and for encryption of short, numerical messages. Each unit with a radio is given a set of matching DRYAD code sheets. A single sheet is valid for a limited time (e.g. 6 hours), called a cryptoperiod.

two-square cipher

Encryption technique

fractionated cipher

Rasterschlüssel 44