Kryptos is a sculpture by the American artist Jim Sanborn located on the grounds of the Central Intelligence Agency (CIA) in Langley, Virginia. Since its dedication on November 3, 1990, there has been much speculation about the meaning of the four encrypted messages it bears. Of the four messages, the first three have been solved, while the fourth message remains as one of the most famous unsolved codes in the world. The sculpture continues to be of interest to cryptanalysts, both amateur and professional, who are attempting to decipher the fourth passage. The artist has so far given two clues to this passage.
The ciphertext on the left-hand side of the sculpture (as seen from the courtyard) of the main sculpture contains 869 characters in total : 865 letters and 4 question marks.
In April 2006, however, Sanborn released information stating that a letter was omitted from this side of Kryptos "for aesthetic reasons, to keep the sculpture visually balanced".[3]
There are also three misspelled words in the plaintext of the deciphered first three passages, which Sanborn has said was intentional[citation needed][dubious – discuss], and three letters (YAR) near the beginning of the bottom half of the left side are the only characters on the sculpture in superscript.
The right-hand side of the sculpture comprises a keyed Vigenère encryption tableau, consisting of 867 letters.
One of the lines of the Vigenère tableau has an extra character (L). Bauer, Link and Molle[4] suggest that this may be a reference to the Hill cipher as an encryption method for the fourth passage of the sculpture.
FYI ….WW=WILLIAM WEBSTER
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