machine Enigma

Résumé du document

courte présentation de la machine Enigma en anglais

Extraits

[...] The Enigma Machine We are going to present the Enigma Machine to you. Let's put it into context: The German secret service units issued a code book which contains the settings for each day which changed at midnight. All enigma operators within a local network had to set their machines to the code setting of the day so that each of them could encode and decode letters and messages. This is what it looked like: drawing. Now we are going to list the various steps of the enigma machine : First, you had to choose 3 rotors from a box of 5. [...]

[...] The machine consists of four main components: the keyboard, plugboard, lampboard and rotors. Firstly, the operators showed 3 rotors from a box of 5. These rotors were all wired differently and before placing them in the machine the operators reset an inner wheel on the rotor to a marked position on the outer ring. They were then placed in the machine in the order indicated in the code book. Next the rotors where set to the letters of the day. [...]

[...] Then it runs to the rear of the machine. From there, it goes through the 3 rotors and hits a reflector plate. Then, it comes back on a different part finally lighting a lamp at the rear of the machine indicating another letter than the one which was pressed: the enigma machine cannot encode the letter that you press in the first instance. To conclude, the core principles of Enigma are not so much complicated, but the machine was considered as a secure device (and unbreakable) for a long time due to all the possibilities, settings and "randomness" where you could type the same letter multiple times and get different outputs. [...]