http://www.telegraph.co.uk/et?ac=004782403739693&pg=/et/01/4/20/ncyph20.html By Michael Smith Friday 20 April 2001 BRITAIN'S wartime codebreakers could have cracked the German Enigma cipher machine much earlier if they had followed a diagram for the commercial version lodged with the British Patent Office in the mid-1920s, documents released to the Public Record Office show. But the codebreakers did not believe that the German army would have been so stupid as to use the same simple wiring system as the widely available commercial machine for their military equivalents. The Code and Cypher School, commonly known by its wartime home at Bletchley Park, was fully aware of how the commercial machine worked in the mid-1920s. Chiffriermaschinen Aktiengesellschaft, the German company that manufactured it, had offered the British Government commercial Enigma machines at a price of $190 each in June 1924. Britain declined to take up the offer, waiting for the Germans to register it with the British Patent Office. Then they obtained the description of how it worked from the patent officials, including detailed plans of the make-up of the commercial machine.The files show that, contrary to what had previously been thought, British codebreakers were working on the Enigma machine during the 1920s and 1930s. But they did not manage to break the military variant until early 1940 after gaining vital help from the Poles. The Enigma machine looked like a typewriter. Pressing the keys sent an electrical impulse through a series of circuits wired through rotors that moved with each tap of the key, constantly varying the cipher. British codebreakers had made a good deal of progress in breaking the military version but were held up because they could not work out the order in which the typewriter keys were wired into the internal circuits. "The Germans weren't idiots," said Peter Twinn, one of those who broke Enigma. "When they had a perfect opportunity to introduce a safeguard to their machine by jumbling it up, that would be a sensible thing to do." It was not until July 1939, when they met their Polish equivalents who had broken early versions of the machine, that they found out that it was wired alphabetically, A to the first contact, B to the second contact and so on. This was the same as in the diagram attached to the patent application but was so obvious that the codebreakers never even considered it as a possibility. Six months later, codebreakers made their first break into Enigma, something they could have done far earlier if they had only tried the alphabetical system in the patent application."It was such an obvious thing to do, really a silly thing to do, that nobody ever thought it worthwhile trying it," said Mr Twinn. ISN is hosted by SecurityFocus.com --- To unsubscribe email LISTSERVat_private with a message body of "SIGNOFF ISN".
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