Encrypt and Decrypt with Mathematical Precision
The Affine Cipher is a type of monoalphabetic substitution cipher that combines the multiplicative and additive ciphers. It uses mathematical functions to encrypt and decrypt messages, making it more secure than simple substitution ciphers.
Encryption: E(x) = (ax + b) mod 26 |
Decryption: D(x) = a⁻¹(x - b) mod 26
Frequently Asked Questions
❓ What is an Affine Cipher?
The Affine Cipher is a type of monoalphabetic substitution cipher that uses mathematical functions for encryption and decryption. Each letter in the plaintext is mapped to its numeric equivalent, encrypted using a mathematical function, and then converted back to a letter.
❓ Why must Key A be coprime with 26?
Key A must be coprime with 26 (have a greatest common divisor of 1) to ensure that the modular inverse exists. Without this property, decryption would be impossible as we couldn't reverse the encryption process.
❓ How secure is the Affine Cipher?
The Affine Cipher is not secure by modern standards. With only 312 possible key combinations (12 values for A × 26 values for B), it can be easily broken using brute force attacks or frequency analysis. It's mainly used for educational purposes to understand basic cryptographic concepts.
❓ What is frequency analysis?
Frequency analysis is a cryptanalysis technique that studies the frequency of letters or groups of letters in a ciphertext. In English, certain letters (like E, T, A) appear more frequently than others. By comparing the frequency distribution in ciphertext to typical English, cryptanalysts can break substitution ciphers.
❓ Can I use this tool for real encryption?
While this tool accurately implements the Affine Cipher, it should not be used for securing sensitive information. The Affine Cipher is easily breakable and is only suitable for educational purposes or low-stakes applications where security is not a concern.