Alan Turing and the Enigma Machine

Hello everyone, fancy seeing you here (figure of speech). I recently went on a trip to Cambridge with a friend and my grandparents. As part of the Cambridge University lectures, Dr. James Grime (who is actually a public speaker) spoke to us (the audience) for an hour about the life and death of Alan Turing and the work done at Bletchley Park during the war. I am still astounded by the complexity of the Enigma Machine, yet I am still pondering whether such inventions could ever match the ability of the human brain. What do you think? Turing's Bombe Machine may certainly have come very close to uncovering the codes and secret messages conjured by the human mind, but I am still not convinced that these early 'computers' could compete with the depth of our mind.

Just an arty snapshot of my train tickets

Here is the what the ticket for the talk looks like....

I'm going to attempt to explain some of the complex layers of the Enigma Machine covered within the lecture ( and if you ever read this blogpost, Dr. James Grime, I apologise in advance for any inaccuracies). I am basing my explanation of the Enigma Machine on the model that Dr. Grime had brought along to the lecture, which was actually lent to Dr. Grime (as he is also part of the Millennium Mathematics Project). That particular Enigma Machine was around 70 years old and was found in a field (if my memory serves me correctly). I suppose I should inform those who are unaware that these machines are most famously known for military code-breaking and making, but these machines also had commercial uses (by banks and big businesses). The machines themselves consist of three rotors, a lampboard, keyboard and plugboard. Doesn't it seem so simple? Trust me, after an hour of having the Enigma Machine and its components explained to us, I can promises you that this is not an easy machine.

The three rotors each have 26 potential turns to it, relating to the number of letters in the alphabet. But, they also have specifically numbered positions that the rotors can be placed in, (and here the complication starts). The lampboard consists of an arrangement of small bulbs (which light up, if that didn't seem obvious enough for you). Basically, whenever a letter is pressed on the keyboard, a different letter lights up on the lampboard, which corresponds with the position of the rotors and the plugboard. The second letter that lights up is the 'code letter' and as you continue to type out your secret message, the machine encrypts it. The coded letter that lights up on the lampboard depends on the rotor settings and the plugboard. Now the plugboard is located at the front of the machine and basically consists of wires that are connected to a pair of letters (e.g. : A and F could be connected together and so on). So, an enigma machine's cryptographic key has several aspects:

• Wheel order - the choice of the rotors and in which order they are fitted (bare in mind that the enigma machine could potentially have more than three rotors)
• Initial position of the rotors - during the War, the German operators would choose this particular setting, firstly from a 'codebook' that they all had which changed settings for every day of the month, then with a secret setting that they would type (in code) at the beginning of the message.
• Ring setting - the position of the alphabet ring relative to the rotor wiring.
• Plugboard connections- these connections would also be stated within the codebook, making it slightly easier for cryptographers to de-code the message. 

Here we have the famous Enigma Machine