Enigma Machine Essay, Research Paper

Enigma Machine

The German Light Cruiser Magdaboard ran around the Baltic sea, the

Russians that were in that area captured the ship and found in it the German

Navy Secret code book. The British used it to decode German Navel messages,

so that they would know what the German s were going to do next.

When the war was over the British told the world that they had found the

Germans code book, which made the Germans realize that code books were not

a good way of getting such important messages around. So they decided that

they needed a code machine.

In Berlin man made an encoding machine available on the market, named

the Enigma Variations. You press a letter on the keyboard and a different letter is

typed. Each time you press that letter the letter that comes out changes. It has

so many approximately 3(10114) different variations.

The Polish had the insight that the codes could be deciphered by

mathematicians. Bartramp photographed the keys to break Enigma s codes, and

sold them to the Polish. The Germans later added two more roters, and they

found out that they needed help, so they brought a bunch of really smart people

together to see if any of them could find a way to break the codes.

One man found a way to build a machine that would take the encoded

message and come up with every possible out come for it. And all they would

need to do is look through them and find out the one that makes sense. All the

mathematicians couldn t break it, and this was the only way that they found that

was possible! “The work of Enigma required enormous concentration and at least eighty

intercepts collected on the same day, using the same setting on the German

cipher devices” [Kozaczuk]. This machine looks alot like a typewriter, but it has

an extra panel built into the lid. Twenty-six circular glass windows in the panel,

were the keys which had the letters of the alphabet on them, just like the

keyboard. On the inside of the panel under the glass buttons there was a

identical number of glowlamps. Inside of the machine was a set of rotors, also

known as rotating drums, and a “reversing drum” that were all mounted on the

same axle. A complex system of wiring included this axle, i guess you coluld say

that it was one of it s main parts. This machine was powered by a battery or an

electrical outlet which passed through a small transformer, so that the power

wasn t to great.

The operator of the machine presses a key, and the ENIGMA machine

produces its substitution, then a lightbulb under one of the letters turns on. The

person then copies down the letter associated with the lightbulb and the next

letter of the message is “typed.” The process is repeated until all leters in the

input message have been typed. The way this can happen is because of the

rotors. For example if you press the letter A it may give out the letter C, then if

you press the letter A again it may give you the letter T, and so on.

The rotor is simply a letter-substitution piece built into the machine. On

one side of the rotor there are 26 contacts representing the 26 letters of the

alphabet, and those 26 contacts are wired to 26 different contacts on the other

side of the rotor. If the lamps are connected to the 26 contacts on the other side

of the rotor, that positioning would be a performance of a simple mapping cipher.

However, instead of the lamps, the rotor’s output connectors are connected to

another rotor. The second rotor provides a second mapping. Then, that rotor is

connected to yet a third rotor, providing three levels of substitution. In some

cases there are even more than just three rotors, there can be five, ten, or even

more.

Each of the rotors has a notch on it that causes the next rotor in the series

to move by one position whenever the notch passes by the indicated letter. The

effect of this rotation is that after each letter is encrypted, an entirely new letter

map is used to map the next letter. Each letter in the output message has its own

map associated with it, and because the rotors are moved with each letter, the

letter mapping depends on not only the letter value, but its position in the

message as well. This combination makes the ENIGMA Machine much stronger

than other cipher machines.

The one weakness of the ENIGMA Machine was that the rotors were fixed

and there wern t very many of them. Once the allies had stolen a couple of

ENIGMA machines and had a full set of rotors, cracking the code became a

matter of trying different combinations of the available rotors until the correct

ones were found. However, the ENIGMA’s good, brilliant design was the basis of

the strongest encryption available for many years after the war ended.