Kasiski Examination

Find repeated sequences to determine cipher key length for polyalphabetic ciphers.

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Cipher Decipher

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Kasiski Examination:

Finds repeated sequences of 3-6 characters in ciphertext
Calculates distances between repeated sequences
Identifies common factors of distances as potential key lengths
Essential for breaking Vigenère and other polyalphabetic ciphers

Method: Developed by Friedrich Kasiski in 1863

Used to determine key length of repeating-key ciphers by analyzing spacing patterns.

Key Length Analysis

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