The Enigma Enigma: How The Enigma Machine Worked
Dec 26, · Enigma machines are a sequence of rotor cipher machines that were developed and used to protect military, diplomatic, and commercial communications during the early-to-mid twentieth century. The device was invented by Arthur Scherbius, a German engineer, after the First World War ended. He managed to set up his Cipher Machine Corporation in in Berlin which produced the Author: Geoffrey Migiro. Nov 09, · The Enigma was used solely to encipher and decipher messages. In its standard form it could not type a message out, let alone transmit or receive it. Author: Alan Stripp.
The Enigma machine is a cipher device developed and used in the early- to midth century to protect commercial, diplomatic, and military communication. The Germans believed, erroneously, that use of the Enigma machine enabled them to communicate securely and thus enjoy a huge advantage in World War II. The Enigma machine was considered to be so secure that even the most top-secret messages were enciphered on its electrical circuits.
Enigma has an electromechanical rotor mechanism that scrambles the 26 letters of the alphabet. In typical use, one person enters text on the Enigma's keyboard and another person writes down which of 26 lights above the keyboard lights up at each key press. If plain text is entered, the lit-up letters are the encoded ciphertext. Entering ciphertext transforms it back into readable plaintext.
The rotor mechanism changes the electrical connections between the keys and the lights with each keypress. The security of the system depends on a set of machine settings that were generally changed daily during the war, based on secret key lists distributed in advance, and on other settings that were changed for each message.
The receiving station has to know and use the exact settings employed by the transmitting station to successfully decrypt a message. While Germany introduced a series of improvements to Enigma over the years, and these hampered decryption efforts to varying degrees, they did not prevent Poland from cracking the machine prior to the war, enabling the Allies to exploit Enigma-enciphered messages as a major source of intelligence. Several different Enigma models were produced, but the German military models, having a plugboardwere the most complex.
Japanese and Italian models were also in use. With its adoption in slightly modified form by the German Navy in and the German Army and What communication skills are important Force soon after, the name Enigma became widely known in military circles. Pre-war German military planning emphasized fast, mobile forces and tactics, later known as blitzkriegwhich depend on radio communication for command and coordination.
Since adversaries would likely intercept radio signals, messages had to be protected with secure encipherment. Compact and easily portable, the Enigma machine filled that need. Around DecemberMarian Rejewskia Polish mathematician and cryptanalystwhile working at the Polish Cipher Bureauused the theory of permutations and flaws in the German military message encipherment procedures to break the message keys of the plugboard Enigma machine.
Rejewski achieved this result without knowledge of the wiring of the machine, so the result did not allow the Poles to decrypt actual messages. The French spy Hans-Thilo Schmidt obtained access to German cipher materials that included the daily keys used in September and October Those keys included the plugboard settings.
The French passed the material to the Poles, and Rejewski used some of that material and the message traffic in September and October to solve for the unknown rotor wiring. Consequently, the Polish mathematicians were able to build their own Enigma machines, which were called Enigma doubles. The Polish Cipher Bureau what did woz call his first computer back in 1972 techniques to defeat the plugboard and find all components of the daily key, which enabled the Cipher Bureau to read German Enigma messages starting from January Over time, the German cryptographic procedures improved, and the Cipher Bureau developed techniques and designed mechanical devices to continue reading Enigma traffic.
As part of that effort, the Poles exploited quirks of the rotors, compiled catalogues, built a cyclometer to help make a catalogue withentries, invented and produced Zygalski sheets and built the electro-mechanical cryptologic bomba to search for rotor settings. Inthe Germans added complexity to the Enigma machines, leading to a situation that became too expensive for the Poles to counter. The Poles had six such bomby plural of bombabut when the Germans added two more rotors, ten times as many bomby were then needed, and the Poles did not what year did color tv the resources.
On 26 and 27 July in Pyry near Warsawthe Poles initiated French and British military intelligence representatives into their Enigma-decryption techniques and equipment, including Zygalski sheets and the cryptologic bomb, and promised each delegation a Polish-reconstructed Enigma.
The demonstration represented a vital basis for the later British continuation and effort. The Poles were taken across the border into Atkins' native Romania, at the time a neutral country where some of them were interned. Atkins arranged for their release and onward travel to Western Europe to advise the French and British, who at the time were still unable to decrypt German messages. Gordon Welchmanwho became head of Hut 6 at Bletchley Park, has written: "Hut 6 Ultra would never have gotten off the ground if we had not learned from the Poles, in the nick of time, the details both of the German military version of the commercial Enigma machine, and of the operating procedures that were in use.
During the war, British cryptologists decrypted a vast number of messages enciphered on Enigma. The intelligence gleaned from this source, codenamed " Ultra " by the British, was a substantial aid to the Allied war effort. Though Enigma had some cryptographic weaknesses, in practice it was German procedural flaws, operator mistakes, failure to systematically introduce changes in encipherment procedures, and Allied capture of key tables and hardware that, during the war, enabled Allied cryptologists to succeed and "turned the tide" in the Allies' favour.
Like other rotor machines, the Enigma machine is a combination of mechanical and electrical subsystems. The mechanical subsystem consists of a keyboard ; a set of rotating disks called rotors arranged adjacently along a spindle ; one of various stepping components to turn at least one rotor with each key press, and a series of lamps, one for each letter.
These design features are the reason that the Enigma machine was originally referred to as the rotor-based cipher machine during its intellectual inception in An electrical pathway is a route for current to travel. By manipulating this phenomenon the Enigma machine was able to scramble messages. When a key is pressed, one or more rotors rotate on the spindle. On the sides of the rotors are a series of electrical contacts that, after rotation, line up with contacts on the other rotors or fixed wiring on either end of the spindle.
When the rotors are properly aligned, each key on the keyboard is connected to a unique electrical pathway through the series of contacts and internal wiring. Current, typically from a battery, flows through the pressed key, into the newly configured set of circuits and back out again, ultimately lighting one display lampwhich shows the output letter.
For example, when encrypting a message starting ANX The operator would next press Nand then X in the same fashion, and so on. Current flows from the battery 1 through a depressed bi-directional keyboard switch 2 to the plugboard 3. Next, it passes through the unused in this instance, so shown closed plug "A" 3 via the entry wheel 4through the wiring of the three Wehrmacht Enigma or four Kriegsmarine M4 and Abwehr variants installed rotors 5and enters the reflector 6.
The reflector returns the current, via an entirely different path, back through the rotors 5 and entry wheel 4proceeding through plug "S" 7 connected with a cable 8 to plug "D", and another bi-directional switch 9 to light the appropriate lamp. The repeated changes of electrical path through an Enigma scrambler implement a polyalphabetic substitution cipher that provides Enigma's security.
The diagram on the right shows how the electrical pathway changes with each key depression, which causes rotation of at least the right-hand rotor. Current passes into the set of rotors, into and back out of the reflector, and out through the rotors again.
The greyed-out lines are other possible paths within each rotor; these are hard-wired from one side of each rotor to the other. The letter A encrypts differently with consecutive key presses, first to Gand then to C. This is because the right-hand rotor steps rotates one position on each key press, sending the signal on a completely different route. Eventually other rotors step with a key press. The rotors alternatively wheels or drumsWalzen in German form the heart of an Enigma machine.
Each rotor is a disc approximately 10 cm 3. The pins and contacts represent the alphabet — typically the 26 letters A—Z, as will be assumed for the rest of this description.
When the rotors are mounted side by side on the spindle, the pins of one rotor rest against the plate contacts of the neighbouring rotor, forming an electrical connection. Inside the body of the rotor, 26 wires connect each pin on one side to a contact on the other in a complex pattern. Most of the rotors are identified by Roman numerals, and each issued copy of rotor I, for instance, is wired identically to all others.
The same is true for the special thin beta and gamma rotors used in the M4 naval variant. By itself, a rotor performs only a very simple type of encryptiona simple substitution cipher. For example, the pin corresponding to the letter E might be wired to the contact for letter T on the opposite face, and so on. Enigma's security comes from using several rotors in series usually three or four and the regular stepping movement of the rotors, thus implementing a polyalphabetic substitution cipher.
Each rotor can be set to one of 26 possible starting positions when placed in an Enigma machine. After insertion, a rotor can be turned to the correct position by hand, using the grooved finger-wheel which protrudes from the internal Enigma cover when closed. In order for the operator to know the rotor's position, each has an alphabet tyre or letter ring attached to the outside of the rotor disc, with 26 characters typically letters ; one of these is visible through the window for that slot in the cover, thus indicating the rotational position of the rotor.
In early models, the alphabet ring was fixed to the rotor disc. A later improvement was the ability to adjust the alphabet ring relative to the rotor disc. The position of the ring was known as the Ringstellung "ring setting"and that setting was a part of the initial setup needed prior to an operating session. In modern terms it was a part of whats going on with lamar odom initialization vector.
Each rotor contains one or more notches that control rotor stepping. In the military variants, the notches are located on the alphabet ring. The Army and Air Force Enigmas were used with several rotors, initially three. On 15 Decemberthis changed to five, from which three were chosen for a given session. This variation was probably intended how to make arroz caldo pinoy style a security measure, but ultimately allowed the Polish Clock Method and British Banburismus attacks.
The Naval version of the Wehrmacht Enigma had always been issued with more rotors than the other services: At first six, then seven, and finally eight. The four-rotor Naval Enigma M4 machine accommodated an extra rotor in the same space as the three-rotor version. This was accomplished by replacing the original reflector with a thinner one and by adding a thin fourth rotor.
That fourth rotor was one of two types, Beta or Gammaand never stepped, but could be manually set to any of 26 positions. One of the 26 made the machine perform identically to the three-rotor machine. To avoid merely implementing a simple solvable substitution cipher, every key press caused one or more rotors to step by one twenty-sixth of a full rotation, before the electrical connections were made.
This changed the substitution how to have nice skin on body used for encryption, ensuring that the cryptographic substitution was different at each new rotor position, producing a more formidable polyalphabetic substitution cipher.
The stepping mechanism varied slightly from model to model. The right-hand rotor stepped once with each keystroke, and other rotors stepped less frequently. The advancement of a rotor other than the left-hand one was called a turnover by the British. This was achieved by a ratchet and pawl mechanism.
Each rotor had a ratchet with 26 teeth and every time a key was pressed, the set of spring-loaded pawls moved forward in unison, trying to engage with a ratchet. The alphabet ring of the rotor to the right normally prevented this. As this ring rotated with its rotor, a how to make coffee foam machined into it would eventually align itself with the pawl, allowing it to engage with the ratchet, and advance the rotor on its left.
The right-hand pawl, having no rotor and ring to its right, stepped its rotor with every key depression. Similarly for rotors two and three. For a two-notch rotor, the rotor to its left would turn over twice for each rotation. The position of the notch on each rotor was determined by the letter ring which could be adjusted in relation to the core containing the interconnections.
The points on the rings at which they caused the next wheel to move were as follows. The design also included a feature known as double-stepping.
An Enigma machine is a famous encryption machine used by the Germans during WWII to transmit coded messages. An Enigma machine allows for billions and billions of ways to encode a message, making it incredibly difficult for other nations to crack German codes during the war — for a time the code seemed unbreakable. Aug 22, · Possibly the greatest dedicated cipher machine in human history the Enigma machine is a typewriter-sized machine, with keyboard included, that the Germans used to encrypt . Dec 26, · What Did the Enigma Machine Do? Essentially, the Enigma Machine did the same work as any other cipher machine; it facilitated the encryption of classified communication. In other words, it coded and decoded messages that were then transmitted over thousands of miles.
When the official British history of the First World War revealed that German messages were deciphered, in the German army realized that a more secure encryption system was required. The Germans eventually acquired about 30, Enigma machines with a slightly more complex design than commercially available. To create the encrypted text, the unencrypted text was written by the machine, then the encrypted text formed was transmitted by the radio, and the recipient was simply writing the coded message.
The machine produced the deciphered text by itself. Moreover, the system was almost unbreakable unless the daily key settings were captured. This part was not rotating, so it was ensured that the encrypted text was automatically sent back on the rotor discs.
While typing the transcribed text, the encrypted text was produced mechanically at the same time. Each rotor contained 26 letters of the alphabet and was set to any starting position from A to Z based on the daily key. Since , there were five rotors in the machines. There were 26 contacts on each face of the rotor disc, and they were connected to 26 different contacts on the back.
Each rotor was connected differently. At first, the Enigma machine could only change six letters before reaching the starting point.
However, a wider plugboard developed in increased this figure to The German army was publishing a new daily key list every month. The book listed the settings that operators should apply every day on all Enigma machines in each army unit.
According to the daily key list, operators rearrange the rotor discs every morning by adjusting their orientation and also changing the plugboard settings. Due to the combination of these systems, a total of 10 billion calculations had to be made to solve one encryption.
They were doing it repeatedly to ensure stability. If the daily key requires B-M-Q, a randomly selected three-letter combination could precede the second signal, such as S-T-P-S-T-P, and the receiver had to adjust the rotors accordingly. To create encrypted text , the unencrypted text had to be typed on the machine. The text created was transmitted by radio, and the recipient was only typing the coded message. The machine was producing the deciphering text by itself.
Due to the fact it was using by German army, Enigma Machine seen as a system that could not be broken by anyone. Schmidt continued to provide daily keys over the next few years. But the French made little use of them. Poland opened the door. Through an agreement with France, most of the materials related to Enigma were transferred to the Poles, and they began to make copies of the machine.
It was a stimulating idea. In the later years, many mathematicians who were familiar with the German language emerged from the Polish lands which were previously occupied by Germany. Among them was Marian Rejewski. When he had access to a sufficient number of messages per day, he managed to draw a table for the relationships between the first and fourth, second and fifth, third and sixth letters in the message key. By examining these tables, he determined the chains, that is, how many links there were before the first letter was attached to itself — in this case, there were three links, A-U, U-S, S-A.
Rejewski realized that the plugboard settings could not be determined, but the number of links in each chain was a reflection of the rotor settings. Some chains were long, some were short. Rejewski and his colleagues spent a year drawing out the tables for each of the , possible rotor settings, establishing a relationship between them and the lengths of possible chains. Rotor settings were resolved with tables, but plugboard settings were not resolved yet.
When Rejewski and his colleagues began to think they figured out everything they could by using the rotor settings table, one more thing attracted their attention; Sometimes, some messages were clearly understandable:. They realized that some letters might have been switched on the key table.
However, with the introduction of two additional rotors and a larger plugboard in , the Enigma machine again posed a new difficulty. Alan Turing, a young and talented mathematician from Cambridge, was among the diverse employees of the new British decoding center in Bletchley Park. Before joining the center, Turing was working on duality in mathematics, and programmable computers.
It was necessary to work swiftly, as the settings of the Enigma machine were changing at every midnight. If it was not for some clues that were spotted before Turing arrived at Bletchley Park in , the number of settings would probably be too much to work on. As the prototype continued to be tested and developed, the Germans changed the message key protocols, which caused a serious interruption in the decryption.
However, an improved bombe began to be used in August, and by the spring of , 15 more came into use. On a good day, the system could unravel all this in one hour, decoding other signals for the rest of the day. By the end of the war, more than bombes were in use. In , Turing found a shortcut to decrypt Lorenz, an adapted version of the Enigma machine Geheimschreiber that is used by the German navy.
Colossus, a more integrated, programmable digital device, was the real ancestor of the modern computer. As a result of human error and laziness, some Enigma operators have used previously used combinations, instead of completely random message key combinations.
When these were detected, they became useful hints for the decoders and so the signals from those operators could be monitored. The Germans assumed that making sure that no rotor disc was in the same place for two consecutive days made the system safer.
On the contrary, it was providing a weakness; because when the position of one or two rotor discs was determined, the number of possible remaining combinations was greatly decreasing.
Also, it was easier to detect the possible combinations of the next day. Some types of signals were predictable and based on a specific formula. These kind of signals were carefully observed and identified with good predictions. Another crib was to place mines in a particular area and try to trace their geographical coordinates in German submarine messages. Obtaining the German key lists was one of the priorities. During the Atlantic War, both German submarines and airships were raided; key lists were captured and vehicles were sunk so that the Germans were not aware of the losses.
Turing was also working on the question of what would happen if the Germans stopped repeating the message key. Thus, Turing discovered another shortcut. Turing thought he would have the chance to review 17, different possible settings in a short time if he arranged a sufficient number of bombes to run sequentially, each imitating the action of another rotor disc.
But he still needed a mechanical shortcut. He accomplished this by connecting successive machines and building circuits between them. In this way, the existence of a loop was notified by a light bulb in the circuit. Just like Rejewski, Turing put the plugboard problem aside and minimized it. Because with a correct crib, it was possible to obtain a deciphered word containing strange letters, and when these letters were replaced correctly the settings of the plugboard were revealed.
The rotors with alphabet rings can be seen. Reflector This part was not rotating, so it was ensured that the encrypted text was automatically sent back on the rotor discs. Rotors Each rotor contained 26 letters of the alphabet and was set to any starting position from A to Z based on the daily key.
Plugboard Stecker At first, the Enigma machine could only change six letters before reaching the starting point. Keyboard The keyboard was for typing the unencrypted text or received encrypted text. Lampboard They show the encryption of every letter typed by the operator. How is the Enigma machine worked? Women were using the Enigma machine more fluently than men To create encrypted text , the unencrypted text had to be typed on the machine. The operator types the unencrypted text.
The text is transmitted through the machine by electric current. Letters activated on the plugboard are first encrypted here. They later go directly to the first rotor. The following letters pass through the disc and go to a different contact point on the next rotor disc.
Also, the first rotor makes a one-letter turn with each letter typed. The same process is repeated in the second disc, and as soon as the first disc revolves the letter cycle, the second disc also makes a one-letter turn. The same process is repeated in the third disc, and as soon as the second disc revolves the letter cycle, the third disc makes a one-letter turn. Now each letter reaches the reflector and the reflector sends it back with discs through a different path.
The letter moves back from the plugboard to the lampboard. The final encryption is displayed to the operator here. How was the Enigma code broken? Chains By examining these tables, he determined the chains, that is, how many links there were before the first letter was attached to itself — in this case, there were three links, A-U, U-S, S-A. Plugboard Rotor settings were resolved with tables, but plugboard settings were not resolved yet. When Rejewski and his colleagues began to think they figured out everything they could by using the rotor settings table, one more thing attracted their attention; Sometimes, some messages were clearly understandable: CANVAYS EN RAUTE They realized that some letters might have been switched on the key table.
Colossus at Bletchley Park.