"How Mathematicians Helped Win WWII" Topic

"The 1930s saw a reinvigorated Germany begin to re-arm under the leadership of the Nazi Party and Adolf Hitler. This included continuing to build on efforts begun in the 1920s to create secure communications. Germany had suffered significant losses to its submarine fleet in World War I (1914-1918) because of the ability of the Western allies, especially France and Great Britain, to take advantage of weaknesses in the codes and ciphers the Germans had used to try to protect the secrecy of their communications. In addition, a primary reason for the entry of the United States into the war had been the ability of the British to read a secret German diplomatic cable (the Zimmermann Telegraph). The Germans were determined to correct this problem and make sure that in any future war they would be able to pass messages amongst themselves while keeping others from being able to read those messages.

The German military decided in the late 1920s to use a machine that had been built for use by businessmen and made changes to it that would make it more secure, more difficult for an enemy to take advantage of. The machine they used was called the Enigma, and it had been invented by a German engineer named Arthur Scherbius. It originally consisted of a keyboard, a display panel of letters that would light up, and a series of rotors through which electric current would pass. Depressing one of the keys on the keyboard would cause an electric current to pass through the rotors which would rotate in a predetermined fashion and then would cause one of the letters on the display panel to light up. The lit letter would be the cipher value for the letter whose key had originally been pressed…"
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Amicalement
Armand

There was a special on one of the history channel about breaking the Enigma code. There were some tells which allowed the British to break the code. One of them was that one of the operators put Heil Hitler in the same spot in every message.

One weakness was that a code letter couldn't map to itself in the cipher. This gave a way to eliminate a good number of combinations. Also, if it had a code letter that required a new rotor setting within the text. It would make it much more difficult to decipher.

Thanks!.

Amicalement
Armand