23 Oct The Vigenère cipher was thought to be completely unbreakable for hundreds of years, and indeed, if very long keys are used the Vigenère cipher can be unbreakable. But if short keys are us
The Vigenère cipher was thought to be completely unbreakable for hundreds of years, and indeed, if very long keys are used the Vigenère cipher can be unbreakable. But if short keys are used, or if we have a lot of ciphertext compared to the key...