In classical cryptography, the running key cipher is a type of polyalphabetic substitution cipher in which a text, typically from a book, is used to provide a very long keystream. Usually, the book to be used would be agreed ahead of time, while the passage to use would be chosen randomly for each message and secretly indicated somewhere in the message.
Read more about Running Key Cipher: Example, Variants, Security, Confusion
Famous quotes containing the words running, key and/or cipher:
“I abide by a rule concerning reviews: I will never ask, neither in writing nor in person, that a word be put in about my book.... One feels cleaner this way. When someone asks that his book be reviewed he risks running up against a vulgarity offensive to authorial sensibilities.”
—Anton Pavlovich Chekhov (1860–1904)
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