School. He later followed up with his education at Kings College, Cambridge with a study in mathematics. While at Kings College, Turing was elected into a junior fellowship (Holt Codebreaker). During this fellowship, he created the Turing Machine. It’s a very simple machine that runs on top of tapes. Each block would have a single character, such as a number, written on the block (Turing Computing Machinery and Intelligence). Based off of the information and the rules programmed into the machine the “rules determine, from the current state of the finite control and the symbol contained in the cell under scan, the operation to be performed next” (Paul M.B. Vitanyi 58). The Turing Machine became the basis of modern computing. His fellowship was soon cut short due to the outbreak of the Second World War (Hodges The Alan Turing Internet Scrapbook). Turing was recruited to work in Britain’s Government Code and Cipher School at Bletchley Park to work on a top secret mission. Bletchley Park became the core of Ultra which was the top secret code breaking mission ( Apted Enigma). Only a few knew the full extent as to what Ultra was ultimately trying to achieve. Turing, along with a few other cryptanalysis, were assigned to work in hut eight which dealt with the decoding of the naval enigma. The enigma was how the Germans communicated with each other throughout the war. They sent boat placements, weather reports, and plans of action and attack. Since they thought this machine was unable to be decoded, the secret spies used it to communicate back and forth (Underwood Industrialization of Codebreaking). This contraption was a perfunctorily operated electro-magnetic machine. When a letter was typed, it would go through various scramblers and light up a random letter on the light board. However due to the multiple moving parts of the machine, such as its rotors, they would switch positions every time a letter was pressed. This would cause the same letter to light up a different letter on the light board every single time. This made it nearly impossible to solve the cipher machine. To make matters worse, multiple parts of the machine could be programmed in various ways. The machine came with five rotors to choose from which could be set in twenty six various arrangements (Enigma Apted). The rotors then had six hundred and seventy-six ways in which they could move. The final section of the enigma, the plugboard, had ten different cables which hooked up to different pairs of letters. A standard enigma had approximately one hundred and seven million,million,million different possibilities. This made it nearly impossible to decode if you did not have the German key sheet. The key sheet would have the precise way in which the machine would be set up for that day. Fearing the allies might get a hold of the key sheet, the Germans made sure each guide was printed with a soluble solution. It would dissolve in water (Hodges Alan Turing: The Enigma). Even though there were enormous amounts of different variations of programs, one letter was not itself on the plugboard.
The Germans would also start and end messages with the same phrases such as, “weather” or “Heil Hitler”. This would not completely solve the message, but it could help the code breakers in determining how the machine was set up for that day. Since it was impossible to decode these messages by hand, Turing, along with the other cryptologists at Bletchley Park adapted the Polish Bombe machine. A bombe was also an electromagnetic device that was set up similar to the enigma. The bombe was created to determine which rotor was in place, and the order of the rotors. This machine consisted of twelve different rotor variations (Underwood Industrialization of Codebreaking). Turing revised the bombe by also making it recognize certain “cribs”. A crib is an algorithm of letters which match up to the cipher letters. To figure out if a message was lined up correctly, Turing had to make sure a letter did not match up to itself. It was easier to find cribs in the formulaic messages such as the “Heil Hitler” and “weather”. After finding the correct placement of the letters, it would take approximately eighteen minutes to find the correct rotor and then proceed to descramble the message. Alan Turing decoded the enigma and now knew most of the German’s secrets (Turing Computing Machinery and …show more content…
Intelligence). Since the Allies could now secretly decipher the German’s messages, they needed a plan of attack.
The allies decided that the best plan of action would be to trick the German’s into where they would strike next. Historian Ben Macintyre said, “The idea, very simply, was to get a dead body, equip the dead body with false papers, and then drop it somewhere the Germans would find it” ( Dead Man Floating: World War IIs Oddest Operation). Originally, the allies were supposed to invade Sicily. However, the false documents said the allies would invade Greece. Somehow this genius idea worked, and the German troops moved from protecting Sicilian borders to protecting Greek borders. The hoax of an attack saved over a thousand allied lives, overthrew the Italian dictator, and changed the course of the war. After that encounter, Cryptologists were told to focus on the messages being sent back and forth from the German unterseeboots, more commonly referred to as U-boats( Rafferty U-Boat). They were under see boats that the Germans used to secretly attack the Allies. The Allies could now figure out where these boats were going. They could either plan for attacks or get away if they were not prepared. Due to the fact that the allies now had the advantage of knowing where these U-boats were, they could now plan to sink them. This was a crucial part to winning the war. In the end, the Allies sunk about seven hundred and eighty three U-boats. None of this would have been possible without
Alan Turing’s deciphering abilities (Apted Enigma). Despite the fact that the Allies won the war, the secret of the enigma still remained for another thirty years. The cryptologists could not reveal who they were or what their job intended them to do. Despite his war successes, Alan Turing was shunned after the war due to the fact that he was a homosexual. Being a homosexual during this time was illegal. He was labeled as a security threat and was no longer used or wanted for decoding messages. Instead of going to jail, Turing compromised to infuse injections of oestrogen- a chemical castrate. Turing committed suicide a year after the war. It was only in two thousand and thirteen when Queen Elizabeth II abolished his arrest and punishment for good. (NBC Queen Pardons Computing Giant Alan Turing 59 Years after His Suicide).
Winston Churchill said, “Turing Made the Single Biggest Contribution to Allied Victory” (The Turing Centenary Bicentennial). Turing saved over thousands of Allied lives and helped shorten the war by an estimate of two years (NBC Queen Pardons Computing Giant Alan Turing 59 Years after His Suicide).