Enigma Machine

Examples

The following are examples:

• Rotors: (I III V), Rotor start: (WWW), Rings: (BBB), Plugboard: (BA QU CG XT DI ER JW LS VK NM), data="HelloHowAreYou" gives "DXXIQUIJZMNBEH" here
• Rotors: (I-III-V), Rotor start: (ABC), Rings: (XYZ), Plugboard: (BA QU CG XT DI ER JW LS VK NM), data="HelloHowAreYou" gives "YNHWFVJEMWGLVY" here
• Rotors: (I-III-IV), Rotor start: (ABC), Rings: (XYZ), Plugboard: (BA QU CG XT DI ER JW LS VK NM), data="HelloHowAreYou" gives "PKWSGCUAYAMUDG" here
• Rotors: (IV-III-V), Rotor start: (ABC), Rings: (XYZ), Plugboard: (BA QU CG XT DI ER JW LS VK NM), data="HelloHowAreYou" gives "ZMDVVLHGBMXMTN" here
• Rotors: (I-II-III), Rotor start: (AAA), Rings: (ZZZ), Plugboard: (BA QU CG XT DI ER JW LS VK NM), data="HelloHowAreYou" gives "XNNJSANZVAZHBV" here
• Rotors: (I-II-III), Rotor start: (AAA), Rings: (ZZZ), Plugboard: (BA QU CG XT DI ER JW LS VK NM), data="QWERTY" gives "CIJWHI" here

Check [Here]

Rotor names:

I, II, III, IV, V 	All Wehrmacht models
VI, VII, VIII 	    Kriegsmarine M3 & M4
Beta, Gamma 	    Kriegsmarine M4 (with thin reflectors)

Reflector types:

B, C 	        All Wehrmacht models
B-Thin, C-Thin 	Kriegsmarine M4 (with Beta & Gamma rotors)

Theory

The Enigma machine was used in the War where operators re-configured the machines every day with a code book (or key sheet). Each key sheet contained defined the daily Enigma settings over the period of a month. Each day the machine was reconfigured.

Ref: [here]

The key used:

• Rotors to use, and what order to put them into the machine (Walzenlage)
• Ring settings for each rotor (Ringstellung)
• Pugboard connections (Steckerverbindungen)
• Special text fragments that need to be transmitted to identify the transmitters key (Kenngruppen)

There is also a reflector setting which is normally fixed and does not change in the field.

When receving a cipher text, the first thing to do is to determine the day that the message was set so that the key can be determined.

The date uses the Kenngruppen (text fragments) to determine the date it was sent, and generate the correct key set.

An example of a keyfile is:

1 II IV V 1 16 10 AV BS CG DL FU HZ IN KM OW RX B
2 I IV V 1 15 10 AC LS BQ WN MY UV FJ PZ TR OK B

Day 1 uses II-IV-V, and rotor rings of 1 16 10, and a mapping of "AV BS CG DL FU HZ IN KM OW RX" and Reflector of "B".

Day 2 uses I-IV-V, and rotor rings of 1 15 10, and a mapping of "AC LS BQ WN MY UV FJ PZ TR OK" and Reflector of "B".