Ciphers are arguably the corner stone of cryptography. In general, a cipher is simply just a set of steps (an algorithm) for performing both an encryption, and the corresponding decryption. Despite might what seem to be a relatively simple concept, ciphers play …

Understand the fine details of a wide range of cryptographic ciphers. Find information on block ciphers, symmetric ciphers, public key encryption, and many more. Cryptanalysis

Invented by Lester S. Hill in 1929, the Hill cipher is a polygraphic substitution cipher based on linear algebra. Hill used matrices and matrix multiplication to mix up the plaintext. To counter charges that his system was too complicated for day to day use, Hill constructed a cipher machine for his system using a series of geared wheels and ...

To encipher messages with the Enigma cipher (or another cipher, see here for documentation), see the example here. Cryptanalysis § For some code to automatically breaking Enigma messages see Cryptanalysis of Enigma .

Here is a quick example of the encryption and decryption steps involved with the caesar cipher. The text we will encrypt is "defend the east", with a key of "ROUNDTABLECFGHIJKMPQSVWXYZ". The first step is to encode our string as Morse code with 'x' between characters and 'xx' between words

The Porta Cipher is a polyalphabetic substitution cipher invented by Giovanni Battista della Porta. Where the Vigenere cipher is a polyalphabetic cipher with 26 alphabets, the Porta is basically the same except it only uses 13 alphabets.

Code is provided for encryption, decryption and cryptanalysis. Homophonic Substitution Cipher. The Homophonic Substitution cipher is a substitution cipher in which single plaintext letters can be replaced by any of several different ciphertext letters. They are generally much more difficult to break than standard substitution ciphers. Four ...

Deciphering is performed in an identical fashion, i.e. encryption and decryption using the beaufort cipher uses exactly the same algorithm. This process can be compared to the Vigenère cipher , which uses a different algorithm, but the same tableau, for finding the ciphertext characters.

ROT13 Cipher Introduction § The ROT13 cipher is a substitution cipher with a specific key where the letters of the alphabet are offset 13 places. I.e. all 'A's are replaced with 'N's, all 'B's are replaced with 'O's, and so on. It can also be thought of as a Caesar cipher with a shift of 13.

Here is a quick example of the encryption and decryption steps involved with the simple substitution cipher. The text we will encrypt is 'defend the east wall of the castle'. Keys for the simple substitution cipher usually consist of 26 letters (compared to …