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:
“Do but consider this small dust, here running in the glass,
By atoms moved.
Could you believe that this the body was
Of one that loved?
And in his mistress’ flame playing like a fly,
Turned to cinders by her eye?
Yes, and in death as life unblest,
To have’t expressed,
Even ashes of lovers find no rest.”
—Ben Jonson (1572–1637)
“Woe unto you, lawyers! for ye have taken away the key of knowledge: ye entered not in yourselves, and them that were entering in ye hindered.”
—Bible: New Testament Jesus, in Luke, 11:52.
“It is not an arbitrary “decree of God,” but in the nature of man, that a veil shuts down on the facts of to-morrow; for the soul will not have us read any other cipher than that of cause and effect. By this veil, which curtains events, it instructs the children of men to live in to-day.”
—Ralph Waldo Emerson (1803–1882)