History of Computers - Enigma and Turing
Created by: Chris Randall
Introduction
The Poles had broken Enigma in 1932, when the encoding machine was undergoing trials with the German Army. But when the Poles broke Enigma, the cipher altered only once every few months. With the advent of war, it changed at least once a day, giving 159 million million million possible settings to choose from. The Poles decided to inform the British in July 1939 once they needed help to break Enigma and with invasion of Poland imminent.[1].
Overview
Arthur Scherbius, a German engineer, developed his 'Enigma' machine, capable of transcribing coded information, in the hope of interesting commercial companies in secure communications. In 1923 he set up his Chiffriermaschinen Aktiengesellschaft (Cipher Machines Corporation) in Berlin to manufacture his product. Within three years the German navy was producing its own version, followed by the army in 1928 and the air force in 1933.[2]. Enigma allowed an operator to type in a message, then scramble it by using three to five notched wheels, or rotors, which displayed different letters of the alphabet. The receiver needed to know the exact settings of these rotors in order to reconstitute the coded text. Over the years the basic machine became more complicated as German code experts added plugs with electronic circuits.
Significance
The significance of the enigma code was how it pushed Alan Turing, an English mathematician, to create a computer to crack the code. Turing’s ‘bombe’, or decoding machine, attacked the message text by means of a ‘crib’ – words likely to occur in the message. Cribs resulted from the stereotyped nature of the messages and the insecure habits of some operators. Weather stations regularly sent messages beginning ‘WETTER FUER DIE NACHT’ (‘Weather for the night’). [3]. In its mature form, the bombe contained thirty-six replica Enigma machines, with ten miles of wire and a million soldered connections. The prototype, named ‘Victory’, was installed in March 1940 at Britain’s codebreaking HQ, Bletchley Park (BP). By November 1941 there were fifteen bombes: at the end of the war there were several hundred. 1942 saw BP decoding 39,000 Enigma messages each month, and 84,000 a month by the autumn of 1943. Turing was pushed to build a better machine to crack the Enigma code, and his creation of the computer threw the world into a new age where computers were now growing into the new fad. Intelligence agencies needed computers to keep up with other nations, and Turing computers were now the forefront of technology.
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