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Enigma
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Attention, the cache is NOT located on the
coordinate mentioned above!
However you can park your car here.
You can calculate the coordinate of the micro-cache
using the clues given below.
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| Enigma |
 During WWII the Germans used
mechanical devices to encrypt their radio messages. The best known
of these machines is the Enigma, which was initially invented in
1918 for commercial applications, until it was adopted by the
German Army for militairy encipherment. Not many Enigma devices are
available today, but some can be seen in dedicated exhibitions
throughout the world. |
| Working
principle |
| When studying the working principle of the Enigma, we have to
consider that there are in fact many different variants of this
machine. Some of the differences make it impossible to decrypt a
message that was encoded on another model. That does however not
affect the working principle as explained here. For this we study
the circuit diagram of an Enigma M3. |
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Letters are 'scrambled' by a set of rotatable wheels each with
26 contacts on either side. Each contact on one side is connected
(wired) to a contact on the other side in some random fashion. Some
models, like the M3 have 3 such rotating wheels, but the M4 model,
used later in the war during the U-boat war, has 4 wheels. Each
time a key is pressed, the right most wheel is rotated by one step,
resulting in a different mapping of the internal wires. A wheel has
one or more notches that may cause the next wheel to be moved by
one position too. This will result in a different encoding for each
letter entered on the keyboard!
The keyboard consists of 26 keys, marked A-Z. Whenever a key, say
Q, is pressed the wheels will be moved into a new position and a
contact is closed. As a result a current will flow. The wires from
the 26 keys are connected to a static wheel called the Stator or
Entrittswalze (ETW). The order in which the keys are connected to
the 26 contacts on the ETW varies between the different Enigma
models.
Leaving the ETW, the current enters the right most wheel (1) at the
right hand side. The internal wiring of that wheel 'translates'
this to one of the contacts of its left hand side, where it enters
the next wheel, etc. Left of the rotating wheels is the Reflector,
or Umkehrwalze (UKW). This wheel sends the current back into the
rotating wheels, but this time the current flows from left to
right, until it reaches the ETW again. From the ETW the current
goes to the lamp board where the corresponding letter (W in the
example) will be lit. It is inherent to this design, that a letter
can never be encoded into itself.
Before starting the ciphering process, the Enigma needs to be setup
in a known way by both sides. This means the wheel order
(Walzenlage) needs to be known as well as the starting position of
each wheel (Grundstellung). In order to further complicate things,
each wheel has a settable index ring that moves the contacts
independant of the wheel's alphabet. This is called the ring
setting (Ringstellung).
To make life even more complex, some models are equipped with a
plug panel (Steckerbrett) that allows letters to be swapped.
Between none and 13 of such mappings may be added. If a key is not
mapped (i.e. no stecker is used for that key), the letter is known
to be Self-Steckered. See below for more information. |
| Wheel
rotation in more detail |
 First of all, the wheels are
moved into a new position, before the key is encoded and the
lamp is turned on.
Each wheel has 26 positions that we will call A-Z. The index on the
wheels is engraved (either as A-Z or 1-26) along the side of the
wheel. The wheels are rotated clockwise, when viewed from the ETW.
If A was visible in the window, the letter B will be
visible next time the wheel is moved. Each wheel has a ring that
can be used to rotate the wiring independantly of the index. This
can be regarded as creating an offset in the opposite direction.
The notches are fixed to the index. Therefore the turnover of the
next wheel, will always happen at the same letter in the
window.
Furthermore most models are equipped with stepping levers and
notches and will therefore exhibit a double stepping feature (see
below). The Enigma G series however, uses a gear and does not
suffer from the double stepping behaviour. |
| The
Steckerbrett |
 The naval
variants of the Enigma (M3 and M4) were equipped with a
Steckerbrett (plug board or patch panel) that would allow any pair
of letters to be swapped. If a patch cable was used beteen G
and P, those two letters would be swapped. As we have 26
characters, a theoretical maximum of 13 cables could be used. Most
machines however, were supplied with less (e.g. 10 or 11)
cables.
Note that any number of cables can be used, from none to 13, giving
a much increased number of possible permutations. As the
Steckerbrett is connected between the keyboard and the ETW, the
encoded letter will go through stecker mappings twice. This would
prevent a letter of being encoded into itself.
The picture shows single patch cable. To prevent a plug from being
inserted in the wrong way, a thick and a thin pin were used. Two
wires were used to cross-connect the pins of both plugs. |
| Differences
in Enigma models |
It has been stated before that there are many different
versions of the Enigma. The various models may differ in:
- Steckerbrett
Some models have a plug panel and some don't. The theoretical
maximum number of patch cables is 13 (as we have 26 letters), but
the number of cables supplied with the unit varies. The maximum
number of permutations is achieved with 11 patch cables.
- ETW mapping
The Eintrittswalze (ETW) can be mapped in a linear fashion:
ABCDEFGH... etc, but also in the order of the keys on the keyboard:
QWERTZUIO... On the Japanese machine, the Tirpitz, the contacts of
the ETW are organised in a random fashion: KZROUQHY...
- Numbers or letters
Some wheels have numbers (01-26) on their perimeter, whilst others
carry letters (A-Z). Initially all Enigma machines used letters
(A-Z) on their wheels. This is definitely the case for all
commercial Enigma machines produced prior to WWII. When the German
Army adopted the machine for military use, they added a
Steckerbrett (see above) and changed the lettering of the wheels
into numbering (01-26). The (later) Naval machines (M3 and M4)
would have letters again.
- Number of different of wheels
Some models have 3 rotatable wheels, but the M4 has 4 wheels. Also
some models have a range of wheels (e.g. 8) to choose from. The
wheels may be placed in the machine in any particular order. On an
Enigma M4 (a 4 wheel machine), the extra wheel is not moved
automatically, but can be set manually to an initial position.
Furthermore the extra wheel cannot be exchanged with the other
three wheels as it is a 'thin' one. The 4th wheel was supplied as a
pair with an UKW. For UKWs B and C, the extra wheels Beta and Gamma
where supplied, hence the name Griechenwalze (Greek wheel). They
may be used however in any combination. The 4th wheel on an Abwehr
Enigma (G-series) is moved by the other wheels, due to the
mechanical difference of this model.
- UKW mapping and setting
Some models have more than one UKW available. On most models the
UKW is fixed, but on some the UKW can be given a start position.
Additionally, the G models have a movable UKW, which means that the
wheel can be moved by the notches of the wheel next to it.
- Number of notches on each wheel
In the basic situation, each wheel has one notch which, after a
full revolution, causes the next wheel to be stepped by one
position. Some versions have two or even more notches on each
wheel, causing more frequent changeovers of the next wheel. The
three wheels of the Abwehr Enigma have 11, 15 and 17 notches
respectively.
- Single or double stepping
As a result of the mechanical principle of the stepping mechanism,
the middle rotor 'suffers' from a double stepping anomaly as
described in a paper by David Hamer (see below). The G models,
which use a gear box instead, do not suffer from this anomaly.
- Manufacturer
Before and during WWII, the Enigma machines were build by various
manufacturers. Although these machines were mathematically
compatible, there are a few cosmetic differences. Additionally
there are physical differences between the thin wheels from some
manufacturers.
|
More
information about the Enigma on Wikipedia  |
Nederlandse Wikipedia - English
Wikipedia
(klik op de Nederlandse vlag - click on the UK flag) |
| And now to
the cache |
|
The code below was generated using a Naval M3 machine
with serial number M 2114.
Crack this enigma code using all the relevant information
available for this cache and the information you can read about the
enigma on Wikipedia to find the cache coordinate .
Let the Enigma simulator (further down) help you to do the
job.
You can check your answers for this puzzle on
Geochecker.com.
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Attention. I might happen that the micro cache is missing.
Things like this do happen. I think I found a solution to log your
visit in a way that is both acceptable to you and me.
If the micro cache should be missing, please make a picture from
you at the cache location and have a look on the Missing Micro Enigma Logger page I created for
this Mystery Cache. |
ABJCRRIPVLQOUJCXDW
RUGBVHNPKAVGFIWBKT
XZLKYGQICMMKENBMHW
SQEFZVSRNUFSHPCZVI
UBYSBAJVYALACZOSRM
SHYPMKFBNNTPMCHPZA
FOTDESNKRUIUZNAOIH
LKNXQUBYQOMLTGIBMN
AHGHYLRYAJLUYPJBXX
EWZYO
Let op na de oplossing dien je nog te projecteren! en wel 70 m
op 151 graden! Geoc checker geeft oplossing VOOR de
projectie
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| Please click here for
The Enigma
simulator |
|
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Happy code cracking and good luck
GeoBSWEScout.
Just in case applets like the simulator are not
supported (anymore) on Geocaching dot com please click here.
BTW, never give up. It took the Tommies years to crack the
code. You can do better then that!
(The final cache coordinate is an average of 200 measurements
on a GPSmap 60CSx) |
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