The German engineer Arthur Scherbius in 1918 he patented a machine to encrypt messages, enigma, without knowing that it would be used by Nazis during the Second World War to prevent the allies from deciphering their communications. The enigma machine forced the English army to enlist a team of mathematics so that they could decipher German communications. Only the construction of a second appliance by the British, led by the mathematician and logical Alan Turing, named The Bomballowed to deciphering what until then thought they were indecipherable.
The story of Enigma, the car used by the Nazis to hide the messages
In 1918 the engineer Arthur Scherbius He patented a device that can encrypt the messages that was particularly present. The name with which it was presented to the market was enigma and was sold starting from 1923 and although at the time it was considered a practically indecipherable and therefore perfect mechanism for its purpose, it did not become widespread given its very high cost.
The turning point took place when the German army, knowing that during the First World War their encrypted messages had been easily decoded by the British, decided to buy enigma between the 1926 and the 1929 And to use it to encrypt their messages and war communications, so that any interceptions by the allies did not constitute a problem.
Enigma in fact it was like that complex that the allies, although they had entered the possession of one of its specimens, were not able at first to understand how it works and therefore they could not decipher the messages. In fact, the car had a very high number of possible starting combinations And to decipher the message it was necessary to know exactly the one used by the Germans at the time of sending!
The main concept that made the messages of the Nazis indecipherableit was that they changed the setting everydayso that even if at the end of the day the allies had managed to understand the operation, the next day they were to have to redo all the work from Chiefbecause the encryption discovered the previous day was not the same used the next day.
Finally, however, the allies put on a mathematician task force, among which they were present Alan Turing And Gordon Welchman That after months of long work he managed to discover its operation, and for this they will go down in history. The British scientists, however, managed to create a new device, starting from a Polish model called The Bombcapable of deciphering the German codes that was renamed The English bomb. The impact of this machine within the war was such that the same Winston Churchill he estimated that his contribution helped a Reduce the duration of the war of 2-4 years. But how did the indecipherable German machine work?
How the indecipherable enigma machine worked
Enigma had the appearance of a typewriter and consisted of five main elements: the keyboardthe lampsThe switching paneli rotor and the reflector. The keyboard worked in the same way as those of the writing machines: 26 buttons were present with the 26 letters of the alphabet above which could be pressed by the operator. The lamps instead were 26 small portholes with inside the 26 letters of the alphabet able to light up whenever a keyboard button was pressed.
To encrypt a letter It was necessary to press the letter on the keyboard that you wanted to encrypt, after which Enigma he illuminated the porthole the letter to be written in replacement of the original one. The switching panel, present only in military versions, allowed, through a thread, to associate one letter to another: for example if the letters A and B were connected and the keyboard was pressed by the key with the letter A, this, thanks to the switching panel it became B and vice versa. The rotors were gods Discs driving with 26 numbers engraved on the surface, from 0 to 25, each of which associated with a letter from the alphabet. In the initial versions of Enigma three were used, positioned by the operator in line, next to each other. The first was the most right, the second one and the third one left the left.
Every time a key was pressed on the keyboard, the first rotor, the right one, revolved, causing a continuous change in the association between letters. When he completed a tour, the second rotor made a shot forward; In the same way, at the end of the lap of the second, the third also moved. The reflector played a role similar to that of the rotor, but without making a rotation. The letters coupled by the switching panel and the starting number for each rotor represented the initial configurations of the machine; These configurations were changed every night to prevent the allies from finding out. To give an idea of the complexity of the machine, an example is made by the English YouTuber Numberphilewho encrypted his name with Enigma:
From the following example it is possible to observe that in the encrypted word the Y appears twice and this shows us that the N and the AND Present in the original word both have been translated with the Y, which makes it very difficult to understand the encrypted message. In addition, the two AND In the original word, they were codified with two different letters: Y And W.
Those who want to see a copy of enigma in Italy can go to the National Museum Science and Technology Leonardo Da Vinci or al Museum of Pavia electric technique. Instead, those who want to directly experience the mechanism can use Enigma emulatora site that reproduces its operation.
