Enigma Geocoin

This coin is dedicated to Arthur Scherbius (1878-1929), the brilliant inventor of the Enigma cipher machine.

This geocoin is designed to look like a rotor from an Enigma cipher machine and has a coded message on it's back that can be decoded using an Enigma M2114 (aka Kriegsmarine M3).  Fortunately all the machine settings needed to decode this message are provided on the front of the geocoin, so you won't need to risk your life to capture them.  Enigma machines are rare and valueable, many of them were destroyed during the war and very few were ever captured intact.  Luckily today there are several accurate computer simulations of these machines available, so everyone can still have access to one of these rare and once secret cipher machines and try to decode this coin, even though there are only a few real ones still in operating condition.

This geocoin wants to visit difficult puzzle caches around the world, and be discovered by any geocachers who solve Enigma puzzles.  Try to get pictures at famous codebreaking centers past and present.  Especially Biuro Szyfrów (Poland) and Bletchley Park (England) where the Enigma codes were broken.

If you can sucessfully decode the enigma message on the back of this geocoin, try to place or visit this coin at that secret cache's location also.

When the Enigma cipher machine was patented in 1918 it was state of the art, however so were airplanes made from fabric and wood.  Technology advances quickly during wartime and rotor type cipher machines would be rendered obsolete by huge advances in cryptography.  The perfect code can be quickly and easily deciphered by the intended recipient, yet the enemy can not break it even if they have found one of your machines.  The enigma can be set up more than 1.58x10¹¹⁴ ways, so blindly searching and finding this solution is not like finding a needle in a haystack, its more like finding a particular grain of sand somewhere on the earth.

To encrypt or decrypt a message with an Enigma machine the operator would first need to setup his machine.  He would have to know the machine settings to use, these were changed often and usually found in a secret codebook.  Next he would open the Enigma and select the reflector and desired rotors and lock the inner ring of each rotor to the correct position.  Then insert them into the machine in the correct order, close the machine and turn each rotor into the correct starting position for the day.  Each rotor had 26 electrical contacts on each side and the inside of each of the numbered rotors was wired differently.  Then the plug board (Steckerbrett) would then be configured, each of the 10 plugs inserted would transpose two letters of the code with each other.  When a key was pressed electricity would travel through the rotors, and to a reflector, then back through all the rotors again and into the plugboard and light up one of the letters on the lampboard.  After each letter was depressed the rotors would change positions moving like the odometer wheels in a car, totally changing the encryption method used after each letter is input.  Before 1940 the operation of the Enigma once it was set up was relatively simple, The first 6 letters of the coded transmission (like the one on this coin) would be the message starting position coded twice (HEWQZA decodes to GJLGJL) so the operator would know all his machine's settings were correct and the starting position for the coded message.  Now just turn the rotors to GJL and begin decoding the message.  The code would be typed on the keypad and the decoded letters would light up, type a message and get out code, type in code and get out your message.  This double encryption was a mistake and was later elimiated in favor of methods that involved selecting in two random three digit trigrams seting the machine with one and using it to encrypt the second which is the message start positon.  People are not random and operators often chose easy to guess trigrams like their initials. (If you saw HIT JBX the trigrams would probably be HIT LER or BER FJT was almost always BER LIN.)  If you looked the the first message of the day, the operaters often did not bother to move the rotors far from the machine's initial setting, look at several messages and you could often guess those settings.

Several types of Enigma machines were adopted for use by the German military after the end of World War I and they were used widely up until the end of World War II.  After the war remaining machines were sold and used worldwide mainly by diplomats until the 1960s (much to the delight of British code breakers).

Enigma was a strong code, but just like in the story of the fabled warrior Achilles, small weaknesses can bring anything or anyone down if they are overconfident and their attackers are persistant.

The story of breaking the Enigma cipher starts with the French and Polish efforts before World War II.  They could both see the direction Germany was headed and saw the need to decipher encrypted German messages.  A spy working for the French named Hans-Thilo Schmidt passed documents to the French showing how the Enigma worked, and how the Germans were using it.  They showed the French that Enigma could be set up in billions and billions of configurations and there would be no predictable pattern to the ciphers it produced.  They were unable to exploit these documents and passed them to the Polish Biuro Szyfrow (Cipher Bureau).

At the Biuro Szyfrow, three excptional code breakers: Marian Rejewski, Henryk Zygalski and Jerzy Rózicki broke the Enigma's code in 1933.  The biggest weakness of the enigma is that no letter can ever be encoded as itself (example: "VCS" can not be code for the word "WAS" because they both end with an "S").  Encrypting the starting position twice was cryptological  mistake also.  They were able to figure out the wiring pattern for all the rotors.  They broke the coded messages by punching the coded text out on huge sheets of paper and sliding punched sheets of paper with plain text over them until no holes lined up.  Most importantly they invented "the bomba" a electrical device to determine Enigma rotor positions.  In 1939 the Germans  increased the sophistication of the Enigma code, by adding extra rotors and later by transmitting the coded start positon only once, which thwarted further Polish attempts at reading the messages.  In 1939 the Polish turned over all of their work in decrypting Enigma codes to both the French and British code breakers.

The British working at the Government Code and Cipher School (GC&CS) at Bletchley Park broke the new Enigma code in 1940 using hand methods and Alan Turing and Gorden Welchman quickly designed a new version of the "bombe" to determine Enigma rotor settings.  The bombe was an electromachanical device that worked by using a crib suspected to be in the message and rapidly disproving each of the millions of incorrect settings and leaving only the few ones that might be possible.  Over 200 of these devices were built during the war and used at Bletchley Park.  Several excellent books and only a few good movies have been made about the efforts of the several thousand people who worked at Blechley Park to break the Enigma codes.  Many of the details of this important work had been closely guarded secrets for more than 40 years and have only recently been publicized. One of the worlds first digital computers (Colusus) was built to assist in breaking Enigma and Lorenz ciphers at Blechley Park.  Many scholors agree their efforts probably shortened the length of World War II by about two years.

Would you like to solve the secret message on this coin, or just play with an Enigma cipher machine, you can download a very realistic simulator here:  Download a Enigma cipher machine simulator.  If you need a web based simulator, Universal Enigma works but is not as realistic as the standalone simulator.

If you would like to read a quick discription on how actual messages were coded and transmitted, received and decoded after the Germans increased the sophication of the coded messages after 1940.  Read this: Enigma Procedure.

 










Here is the message from the coin if you want to decode it:

SUDS FTTV WBZX PDUM YUCR NPLN OQDU RZLA VGXO GURQ IORH NRDK MAIK VUVC XBSH DELV XIIE HCRM JPQW JIAN TPWN KDRG PBBE KPSP PCZB NTFK UWBY

If you enjoyed using the Enigma machine and want to learn more about it here is a link to a fascinating Nova Documentary on the Enigma Machine. and Part 2 of the Documentary on the Enigma Machine.