Vigenère Cipher
A polyalphabetic substitution encryption scheme introduced in the sixteenth century. It uses a keyword to determine the shift applied to each plaintext letter, so that the same plaintext letter encrypts to different ciphertext letters at different positions, effectively flattening the frequency distribution of individual letters.
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The Vigenère cipher is a polyalphabetic substitution scheme proposed in the 16th century, which uses a keyword to determine the shift amount for each plaintext letter.
The weakness of the Vigenère cipher is that when the key length is short and the ciphertext is long enough, an attacker can infer the key length through the Kasiski test or the index of coincidence, thereby reducing the polyalphabetic problem to multiple single-alphabet problems to crack one by one.
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The Vigenère cipher is a polyalphabetic substitution scheme proposed in the 16th century, which uses a keyword to determine the shift amount for each plaintext letter.
50%UnverifiedThe weakness of the Vigenère cipher is that when the key length is short and the ciphertext is long enough, an attacker can infer the key length through the Kasiski test or the index of coincidence, thereby reducing the polyalphabetic problem to multiple single-alphabet problems to crack one by one.
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