Classical ciphers

Affine cipher

The affine cipher is a type of monoalphabetic substitution cipher, where each letter in an alphabet is mapped to its numeric equivalent, encrypted using a simple mathematical function, and converted back to a letter. The formula used means that each letter encrypts to one other letter, and back again, meaning the cipher is essentially a standard substitution cipher with a rule governing which letter goes to which. As such, it has the weaknesses of all substitution ciphers. Each letter is enciphered with the function (ax + b) mod 26, where b is the magnitude of the shift. (Wikipedia).

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Affine Cipher on Maple

How to encrypt and decrypt the affine cipher using Maple software. Code from Into to Crypto and Coding Theory 2nd ed. by W. Trappe and LC Washington.

From playlist Cryptography and Coding Theory

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Algorithm Archive: https://www.algorithm-archive.org/contents/affine_transformations/affine_transformations.html Github sponsors (Patreon for code): https://github.com/sponsors/leios Patreon: https://www.patreon.com/leiosos Twitch: https://www.twitch.tv/leioslabs Discord: https://discor

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From playlist Mathematics

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From playlist Algebraic geometry I: Varieties

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From playlist Computer - Cryptography and Network Security

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From playlist Algebraic geometry I: Varieties

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