Die Entschlüsselung der ENIGMA, Teil 3 von 3

Encryption is certainly not a 20th-century phenomenon. Similar methods existed even in ancient times. However, the secret texts – also called ciphers – could usually be deciphered relatively quickly. A more complex, almost impossible-to-break, yet manageable encryption was only possible with special encryption machines. One of these supposedly unbreakable machines was the legendary ENIGMA. As already reported in Parts 1 and 2, the "Enigma" was used by the German Wehrmacht to encrypt radio traffic by assigning seemingly arbitrary ciphers to typed letters, which were then radioed to the receiver. The receiver had an identically configured Enigma machine and could reveal the plaintext by typing the ciphers. The story of the "disenchantment" of ENIGMA begins in 1932, when Hans-Thilo Schmidt, a German spy for France under the code name "HE" (Asché), betrayed secret key tables for the months of September and October 1932, as well as the operating instructions and key guide, to the French secret service agent Gustave Bertrand in exchange for money. At that time, only three cylinders (I to III) were in use, and the cylinder positions were only changed quarterly, not daily as they were from October 1936 onwards. The foreign intelligence service of the French secret service forwarded the documents to British and Polish authorities. While the French and British failed to break into the encryption and classified the Enigma as "unbreakable," the 27-year-old Polish mathematician Marian Rejewski, working in the BS4 department responsible for Germany, the "Cipher Office," succeeded in breaking into the Enigma for the first time in 1932. He used a legally purchased commercial machine (presumably the Model C), which – unlike the military Enigma I, which he was still unfamiliar with – had a keyboard equipped with the usual letter order of a German typewriter. Rejewski accidentally discovered the wiring sequence chosen by the Germans for the military version, which almost drove the British codebreaker Dillwyn Knox to despair even in 1939. With this impetus, especially with the now finally known roller wiring, the British cryptanalysts were able to launch a renewed attack on the Enigma at Bletchley Park, about 65 km northwest of London, at the outbreak of the war. The most important tool – in addition to the help of over ten thousand male and female employees – was a special electromechanical machine called the "Turing Bombe," which was based on the Polish "Bomba" and was designed by the English mathematician Alan Turing. This made it possible. This enabled him to drastically reduce the virtually unmanageable number of more than 100 trillion (?) conceivable encryption possibilities. Thus, under the code name "Ultra," he succeeded in continuously breaking messages encrypted by the Luftwaffe and later by the Army using the "Enigma I" code, starting in January 1940, almost throughout the entire Second World War. In 1943, for example, more than 80,000 radio messages were intercepted and deciphered per month, an average of more than 2,500 per day; during the war as a whole, the number was over two and a half million. During World War II, Bletchley Park was a secret military agency for the encryption of coded messages, primarily those of the Germans. It was considered the central location for British cryptanalysis. The "State Code and Cipher School" was located there, which regularly "cracked" secret communications of the Axis powers, especially German Enigma and Lorenz ciphers. Bletchley Park is known for its impact on the course of the war and for the work done there by scientists such as Alan Turing and Dilly Knox. Although this work remained secret until 1974, it had a significant impact on the history of science and technology, especially the history of information technology. A heartfelt thank you to Dr. Viehoff, Managing Director of the Heinz Nixdorf Museum Forum in Paderborn!