Enigma Cipher Machine
1915, two Dutch Naval officers invented a machine to encrypt messages. This became known as the Enigma machine.
Marian Rejewski built his own model of the Enigma machine without having actually seen it.
In 1931, a German traitor told Rejewski that the Germans routinely changed the daily key indicator setting for the codes.
The new machine could run through more than 17,000 indicator settings.
He called this machine, ‘the bomb’. The bomb was used to secretly read the traffic from the German Enigma machines for several years.
The Poles asked their allies, Britian and France to help them with the analysis and codebreaking of the German messages.
Alan Turing, a British mathematician at Bletchley Park thought of a different way of using the ‘bombs’ for testing the German codes. Turing used 180 ‘bombs’ which clicked round letter-by-letter, 20 every second, until they hit the correct one.
Hundreds of code breakers at Blechley Park worked round the clock to decipher the German Enigma communications they intercepted.