The Vigenère cipher is a polyalphabetic substitution. Blaise de Vigenère actually produced a more sophisticated autokey cipher, but through an accident of history his name has become attached to this weaker cipher. The cipher below is not le chiffre indéchiffrable, though it has sometimes been mistakenly called that.
This said, the Vigenère cipher is reasonably secure [...]
This post is part of a series of 47 posts which begins with The Caesar Shift, the latest post in the series is Letter Groups.
Vigenère
This post is part of a series of 47 posts which begins with The Caesar Shift, the latest post in the series is Letter Groups.