By Ricardo Lemos 
Winter 2018, Paris, France. After a long three-hour and ten-minute train ride from Amsterdam, Netherlands, to the French capital, my family and I were back at the hotel and started planning our trips around the City of Lights. Among the incredible places we chose, I couldn’t miss visiting the Musée de l’Armée, an environment dedicated to war and weapons of all shapes and sizes. One in particular caught my attention, however, and that was the Enigma Machine, the main reason I’m writing this article. This device itself carries a long historical trajectory about the evolution of encryption technology, the birth of the computer, and the rise of artificial intelligence as we know it today.
ENIGMA MACHINE – Personal archive photo
A little history
Cryptography means “hidden writing,” and its history dates back to antiquity. The first documented use of cryptography was around 1900 BC in Egypt, when a scribe used non-standard hieroglyphics in an inscription.
Aeneas the Tactician was one of the first Greek writers to write about the art of war. In the 5th century BC, he compiled the methods of cryptography in his 31st chapter of Poliorcetica.
The so-called “Julius Caesar Cipher” or “Caesar Cipher”, which presented one of the most classic encryption techniques, is an example of substitution that simply replaces the letters of the alphabet by moving them three positions forward. The author of the cipher replaced each letter with another three positions further forward in the alphabet. According to the author, this algorithm was responsible for fooling many enemies of the Roman Empire; however, once the key was discovered, like all keys, it lost its functionality.
Also worthy of note are the studies of Blaise de Vigenère, who created a method known as the Vigenère cipher, which uses letter substitution, just like the Caesar Cipher, but with different alphanumeric shift values.
From the Renaissance onwards, cryptology began to be seriously studied in the West and thus various techniques were used and the old monoalphabetic codes were gradually replaced by polyalphabetic ones. Over the centuries, the processes became more complicated and cryptography took off.
In 1919, Dutch engineer Hugo Alexander Koch filed a patent for an electromechanical cryptographic machine. His ideas were adopted by German engineer Dr. Arthur Scherbius, who set up a company in Berlin to manufacture and market a cipher machine for civilian use: the Enigma. Although the company failed, the Enigma machine attracted the attention of the German military, who adopted it and began using it to send and receive messages during World War II.
But I will not delve into the merits of the war and its causes, but rather its effects, such as: the end of the war and its consequences; the liberation of prisoners from concentration camps; the arrest of Nazi officers; the creation of the UN; the beginning of the Cold War and, of course, the invention and evolution of the computer.
All of these consequences of the war are due to a single person, the mathematician Allan Turing, who, over three years of research and data collection and analysis, used all of his intelligence to create a machine capable of defeating the Enigma machine. Through his incredible mathematical ability in statistics and prediction, he managed to develop The Bombe. This machine was used to decipher the messages sent by the German armed forces and encrypted by the Enigma Machine. It deciphered the codes sent, allowing the Germans’ messages to be intercepted and known. The information was then passed on to the Allied countries, who knew exactly where their enemies were on the battlefront.
How Enigma works
The encryption performed by the Enigma machine is simple and clever. Each letter is replaced by another, the trick is that the substitution changes from letter to letter. The machine is powered by an electric battery. When a key on the keyboard is pressed, an electric circuit is closed and a letter on the display lights up, indicating which substitution has been made. In concrete terms, the electric circuit is made up of several elements in a chain. Watch the video explanation with expert Edward Ripley-Duggan:
Conclusion
Finally, computers evolved rapidly for the war effort, allowing the success of military incursions by Allied countries, decreeing the end of World War II and the birth of Artificial Intelligence developed by Alan Turing.
Stay tuned for my next articles on Artificial Intelligence applied to Cybersecurity.
Bibliography
https://en.wikipedia.org/wiki/Cryptography
https://en.wikipedia.org/wiki/Alan_Turing
https://en.wikipedia.org/wiki/Aeneas_Tacticus
