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:
“Sense is a line, the mind is a circle. Sense is like a line which is the flux of a point running out from itself, but intellect like a circle that keeps within itself.”
—Ralph J. Cudworth (1617–1688)
“As soon as you are in a social setting, you better take away the key to the lock of your heart and pocket it; those who leave the key in the lock are fools.”
—Johann Wolfgang Von Goethe (1749–1832)
“The eye is the first circle; the horizon which it forms is the second; and throughout nature this primary figure is repeated without end. It is the highest emblem in the cipher of the world.”
—Ralph Waldo Emerson (1803–1882)