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IEEE Annals of the History of Computing Volume 17 Number 1 -- Reviews

IP.com Disclosure Number: IPCOM000129872D
Original Publication Date: 1995-Apr-30
Included in the Prior Art Database: 2005-Oct-07

Publishing Venue

Software Patent Institute

Related People

PEGGY KIDWELL: AUTHOR [+2]

Abstract

The Reviews department includes reviews of publications, films, audio- and videotapes, and exhibits relating to the history of computing. Full-length studies of technical, economic, business, social, and institutional aspects or other works of interest to Annals readers are briefly noted, with appropriate bibliographic information. Colleagues are encouraged to recommend works they wish to review and to suggest titles to the Reviews editor. ";Babbage and Cryptography. Or, the Mystery of Admiral Beaufort's Cipher,"; Mathematics and Computers in Simulation, Vol. 35, 1993, pp. 327-367.

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THIS DOCUMENT IS AN APPROXIMATE REPRESENTATION OF THE ORIGINAL.

Copyright ©; 1995 by the Institute of Electrical and Electronics Engineers, Inc. All rights reserved. Used with permission.

Reviews

PEGGY KIDWELL, EDITOR

The Reviews department includes reviews of publications, films, audio- and videotapes, and exhibits relating to the history of computing. Full-length studies of technical, economic, business, social, and institutional aspects or other works of interest to Annals readers are briefly noted, with appropriate bibliographic information.

Colleagues are encouraged to recommend works they wish to review and to suggest titles to the Reviews editor.

"Babbage and Cryptography. Or, the Mystery of Admiral Beaufort's Cipher," Mathematics and Computers in Simulation, Vol. 35, 1993, pp. 327-367.

Babbage had planned to write "The Philosophy of Deciphering," but never began it. He left behind copious worksheets which show how much time he spent on cryptography, but what he was doing is very unclear. Ole Franksen has done much to help us evaluate Babbage's cryptographic work and published an interesting and unusual book, Mr. Babbage's Secret: The Tale of a Cipher -- and APL,' in which his discoveries are well documented. In the article reviewed here, he restates some of this work and adds more material with the purpose of illuminating the origin of the Beaufort cipher.

The Vigenere cipher is a stream cipher in which the key stream is a repeated word. Letters are given numerical values -- for example, from O to 25 in a 26-letter alphabet. The plaintext P and keystream K are combined to produce ciphertext C by the rule C = P + K, mod 26. This cipher has been "reinvented" countless times. ~

(Image Omitted: The article raises the question "Did Babbage act as cryptographic expert for the Royal Navy through his friend Beaufort?" No evidence is given -- it is just a conjecture.)

Beaufort gave us the Beaufort Scale of wind strength; he was an influential and resourceful person and has also given his name to the Beaufort cipher, a variant of the Vigenere with the rule C = K - P. mod 26. Decipherment follows the same rule, P = K- C, mod 26, and this could make it easier to use.

Franksen shows that the attribution of the cipher to Beaufort is uncertain. Indeed, David Kahn has recorded that it was published in 1710 by Giovanni Sestri. For Beaufort's rediscovery, there are contemporary references to a publication in a scientific journal, but this seems to be lost. A published explanation of the cipher by Beaufort's colleague, Lieutenant Becher, proves to be Vigenere, and the only firm contemporary attribution is on a card, sold for sixpence, written by Beaufort's son William Morris Beaufort. But Beaufort was an honorable man, and it is likely that he really did reinvent the cipher known by his name.

The article raises the question "Did Babbage act as cryptographic expert for the Royal Navy through his friend Beaufort?" but no evidence is given --...