Inner Workings of the German Enigma

History of the EnigmaThe concept was invented by a German named Albert Scherbius in 1918Scherbius tried to take the machine to the German military but initially they werent interestedA company called Gewerkschaft Securitas bought the patent in 1920 and started manufacturing the EnigmaThe German military became interested in 1925 in order to encrypt radio messages.The military made some enhancements.

What is the EnigmaThe Enigma is an Electro-Mechanical Device used to Encrypt MessagesThe Mechanical properties of the machine were based around gears that would turn as keys were pressed on the typewriter style keyboardThe keyboard would also active electrical switches that would initiate an electrical current from a battery

Components of the EnigmaKeyboardPlug BoardSet of 3 RotorsReflectorLight Board

Enigma KeyboardTypewriter Style Keyboard Used to enter the plaintext message into the machine.

Enigma Plug BoardPlug Board Used to make connections between letters of the alphabet. If a connection was made then the letters would be remapped to each other. If a connection was made between the letter A and M then M would get substituted for A and vise versa.

Enigma RotorsMain Component of the EnigmaFlat disks with 26 electrical connections on one face which correspond to the letters of the alphabet. The 26 electrical connections were mapped to 26 different connections on the opposite face of the rotor.Every rotor had a different mapping of the 26 connectionsEarly Enigma machines used 3 rotors from a set of available rotors. Rotor move in an odometer fashion.Possible Alphabets 26x26x26=17,5763 rotors in 3 positions 3x2x1=6Total Possible Alphabets: 17,576x6=105,456

Enigma Rotor PicturesSet of RotorsRotorDisassembled Rotor

Enigma ReflectorThe Reflector was a component at the end of the array of rotors that would reflect the electrical current back through the rotors in the opposite direction and through a different route.

Enigma Light BoardThe Light Board was used to view the cipher text that was being produced by the machine.

How Does The Enigma WorkThere are a total of 9 permutationsThe key is the initial settings of the machine. Rotors used and in what slot, Plug Board, Etc.

Modern Day EnigmasJava Basedhttp://www.ugrad.cs.jhu.edu/~russell/classes/enigma/

Modern Day EnigmasElectronic (Enigma-E Machine)http://www.xat.nl/enigma-e/

ConclusionThe Enigma was revolutionary in its complexity but also in its ease of use.The efforts used by Governments to crack the Enigma are the basis for modern day cryptography.