Japanese cipher machines. The most famous encryption machines in history: ups and downs

Spy stories are always of great interest to the public. The spirit of adventurism and the incredible ingenuity of secret agents who crack safes and solve super-secret ciphers without any problems captivate the audience. But in fact, at least with the last point, everything is much more prosaic.

30 09 2015
16:19

In the secret services, everyone has their own task - the one with which this particular specialist copes best. And in the field of data encryption, the most effective workers are not people at all, but machines. Let's talk about them.

The most famous encryption machine in the world, which was used by Nazi Germany during the Second World War. It was with her help that the command of the Third Reich transmitted most of the secret information. It was necessary to know the enemy's plans, but it was impossible to capture the one who would tell the secret of Enigma.

Today, decades later, we can explain its structure to anyone in sufficient detail.

The portable device of the 1920s looked like a suitcase, like ordinary typewriters of the time. But in addition to the standard keyboard and rollers that move a sheet of paper, Enigma occupied a significant part of the space electronic and mechanical components.

The machine is based on the work of three rotors and a stepped mechanism that moved one or more rotors when a key was pressed.

A diagram without explanation looks quite complicated, so a brief explanation is required. When the key was pressed, the passing current moved the right rotor. Depending on which letter or symbol came next, the second and third rotors were sequentially shifted (in some models there were 4 rotors). Then the current was reflected from the reflector located in the electric circuit after the rotors, and returned to them, but in a different way, shifting them accordingly. Accordingly, the output was a text consisting of completely different letters than those that were typed by the operator. Due to the constant change in the configuration of the electrical circuit, the cipher turned out to be more reliable, although it was an elementary replacement of one letter for another.

There were several disadvantages to this encryption method, and one of the main ones was the impossibility of encrypting any character through itself. Enigma owed this to the reflector, which helped to make the cipher more difficult, but in the end greatly simplified the work of the decoders.

The deciphering of the Enigma code brought worldwide fame to the person who deciphered its code, Alan Turing. Rather, this is how this fact is mentioned most often. In fact, the British mathematician and cryptographer did not directly participate in the decryption. He developed a mathematical logic apparatus for the Bombe, a machine with the help of which intelligence and counterintelligence specialists had already directly deciphered the code.

If Enigma itself was the size of a typewriter, then Bombe weighed 2.5 tons and was an analogue of a large cabinet with dimensions of 3x2.1x0.6 meters. After the war, all Bombe were destroyed as unnecessary (and to maintain secrecy). It took modern scientists 2 years to restore it - it turned out to be so complicated.

It would be a strange and insecure solution to encrypt all communications, both between rank-and-file units and in the ranks of the command, in one way. Therefore, the second, slightly less famous cipher machine of the Second World War was Lorenz. Unlike the Enigma, this apparatus was very bulky and not suitable for temporary camps and rapid movements, and therefore was installed mainly in large headquarters. Why didn't the Germans, who understood the benefits of mobility, make it more compact? The answer to this is in its purpose - it produced stream encryption using a teletype. A teletypewriter is a device that is a typewriter with the inclusion of electronic elements for transmitting a message over a channel (most often a wired channel).

Photo: Lorenz with and without casing

The same machine could both encrypt and decrypt the text, which was quite risky, but justified, since in the event of command capture, no devices would help. Information was encoded using 12 disks, which were located in two parts of the machine. They were divided into 3 parts - psi-, chi- and mu-disks, each of which had a certain number of contacts. Contacts were changed once a quarter, once a month and once a day, respectively. The message was transmitted using a perforated paper tape (the prototype of modern information carriers), on which it was punched by the machine of the receiving party.

However, for every tricky nut there is a threaded bolt. British intelligence needed to create a machine called the Colossus, which was more powerful (in terms of tasks performed) of the much later Pentium 1996.

This device is sometimes called one of the first computers in the world, although it is not such in the truest sense of the word. Its mechanism contained electronic circuits that performed digital functions, but there was no memory as such - instead, a closed punched tape was used. One and a half thousand vacuum tubes, several operators who replaced each other, a separate room and an incredible footage of punched tape - this is what the installation for deciphering the messages of the German command looked like.

How did she work? Intercepted messages made their way on punched tape and passed through the car at a speed of about 80 km / h. Each character was encoded by 5 areas, in place of which either a hole or a section of the tape could be located. Then, using the Lorenz statistical model built by Bill Tutt, the machine ran the received information through 501 patterns (that's how many of them were identified for this type of encryption) and found matches, analyzing the data and printing out the result. This method has reduced the time spent on decryption from several days to a couple of hours.

You can see how much the machines for creating and breaking secret codes varied greatly in size. In other words, this is exactly the case when breaking is no easier than building.

The series of articles on encryption and decryption technologies will be continued.

Dmitry Potapkin, especially for Obzor.press.

The German cipher machine was called "The Riddle" not for a red word. The story of her capture and the decoding of radio interceptions is legendary, and cinematography contributes a lot to this. Myths and truth about the German encoder - in our material.

As is well known, the interception of messages by the adversary can only be countered by their reliable protection or encryption. The history of encryption goes back centuries - one of the most famous ciphers is called the Caesar cipher. Then attempts were made to mechanize the process of encryption and decryption: the Alberti disc, created in the 60s of the 15th century by Leon Battista Alberti, the author of A Treatise on Ciphers, one of the first books on the art of encryption and decryption, has come down to us.

The Enigma machine used by Germany during World War II was not unique. But it differed from similar devices adopted by other countries by its relative simplicity and mass use: it could be used almost everywhere - both in the field and on a submarine. The history of Enigma dates back to 1917 - then the Dutchman Hugo Koch received a patent for it. Her work consisted in replacing some letters with others due to rotating rollers.

We know the history of decoding the Enigma machine mainly from Hollywood blockbusters about submarines. However, these films, according to historians, have little in common with reality.

For example, the 2000 film U-571 tells about the secret mission of American sailors to capture the Enigma cipher machine aboard the German submarine U-571. The action takes place in 1942 in the North Atlantic. Despite the fact that the film is spectacular, the story told in it does not correspond to historical facts at all. The submarine U-571 was indeed in service with Nazi Germany, but was sunk in 1944, and the Americans managed to capture the Enigma machine only at the very end of the war, and this did not play a serious role in the approach of Victory. By the way, at the end of the film, the creators report historically true facts about the capture of the encoder, but they appeared at the insistence of the film's consultant, an Englishman by birth. On the other hand, the director of the film, Jonathan Mostov, stated that his tape "is a work of art."

European films, on the other hand, try to maintain historical accuracy, but there is also a share of fiction in them. Michael Apted's 2001 film Enigma tells the story of Tom Jericho, a mathematician who has to crack the updated code of a German cipher machine in just four days. Of course, in real life, it took much longer to decipher the codes. At first, the cryptological service of Poland was engaged in this. And a group of mathematicians - Marian Rejewski, Heinrich Zygalski and Jerzy Rozicki - studying obsolete German ciphers, found that the so-called daily code, which was changed every day, consisted of plugboard settings, the order of installation of the rotors, the positions of the rings and the initial settings of the rotor . It happened in 1939, even before the capture of Poland by Nazi Germany. Also, the Polish "Cipher Bureau", created specifically for the "fight" with Enigma, had at its disposal several copies of a working machine, as well as an electromechanical machine Bomba, which consisted of six paired German devices, which helped in working with codes. It was she who later became the prototype for the Bombe, the invention of Alan Turing.

The Polish side managed to transfer its developments to the British special services, which organized further work to crack the "mystery". By the way, for the first time the British became interested in Enigma back in the mid-20s, however, they quickly abandoned the idea of ​​deciphering the code, apparently considering that it was impossible to do so. However, with the outbreak of World War II, the situation changed: largely thanks to the mysterious machine, Germany controlled half of the Atlantic, drowned European convoys with food and ammunition. Under these conditions, Great Britain and other countries of the anti-Hitler coalition definitely needed to penetrate the Enigma riddle.

Sir Alistair Dennison, head of the State School of Codes and Cyphers, which was located in the huge castle of Bletchley Park 50 miles from London, conceived and carried out a secret operation Ultra, turning to talented graduates of Cambridge and Oxford, among whom was the famous cryptographer and mathematician Alan Turing . Turing's work on cracking the codes of the Enigma machine is dedicated to the 2014 film The Imitation Game, released in 2014. Back in 1936, Turing developed an abstract computational "Turing machine", which can be considered a model of a computer - a device capable of solving any problem presented in the form of a program - a sequence of actions. At the school of codes and ciphers, he headed the Hut 8 group responsible for the cryptanalysis of German Navy messages and developed a number of methods for breaking the German cipher. In addition to Turing's group, 12,000 employees worked at Bletchley Park. It was thanks to their hard work that the Enigma codes succumbed to decryption, but it was not possible to break all the ciphers. For example, the Triton cipher worked successfully for about a year, and even when the Bletchley guys cracked it, it did not bring the desired result, since too much time passed from the moment the cipher was intercepted to the information was transmitted to the British sailors.

The thing is that, by order of Winston Churchill, all decryption materials were received only by the heads of intelligence services and Sir Stuart Menzies, who headed MI6. Such precautions were taken so that the Germans did not guess about the disclosure of ciphers. At the same time, these measures did not always work, then the Germans changed the Enigma settings, after which the decryption work began anew.

The Imitation Game also touches upon the relationship between British and Soviet cryptographers. Official London was really not sure about the competence of specialists from the Soviet Union, however, on the personal order of Winston Churchill, on July 24, 1941, materials with the Ultra stamp were transferred to Moscow. True, in order to exclude the possibility of disclosing not only the source of information, but also the fact that Moscow would find out about the existence of Bletchley Park, all materials were disguised as undercover data. However, the USSR learned about the work on the decryption of Enigma back in 1939, and three years later, the Soviet spy John Cairncross entered the State School of Codes and Ciphers, who regularly sent all the necessary information to Moscow.

Many are wondering why the USSR did not decipher the radio intercepts of the German "Riddle", although the Soviet troops captured two such devices back in 1941, and in the Battle of Stalingrad, Moscow had three more devices at its disposal. According to historians, the lack of modern electronic equipment in the USSR at that time affected.

By the way, a special department of the Cheka, dealing with encryption and decryption, was convened in the USSR on May 5, 1921. On account of the employees of the department there were not very many, for obvious reasons - the department worked for intelligence and counterintelligence - advertised victories. For example, the disclosure already in the twenties of the diplomatic codes of a number of countries. A cipher was also created - the famous "Russian code", which, as they say, no one managed to decipher.

As we remember, the storyline of the film "From Russia with Love" revolved around a decoder, with the help of which access to Soviet state secrets was opened. What was James Bond after and was it worth it?

Sly Herodotus

From time immemorial, the success of many military operations depended on the accuracy and timeliness of information about the enemy. Therefore, the quality of intelligence (read "espionage") has always been put at the forefront. To protect against interception, important information must be encrypted with high quality. The best minds have always been thrown at solving this problem. For example, even Caesar used a specific cipher for secret correspondence: each character of the message was replaced by another, separated from it by a certain number of positions in the alphabet.

Another ancient genius - Herodotus - was much more resourceful in his encryption research. One day, he created a secret message in the form of a tattoo on the shaved head of a slave. The bald head was covered with fresh hair growth, under which the message was not visible. In the same place - in the homeland of Herodotus - almost the first spy gadget - a wanderer - was invented. It was a wand that was used for permutation encryption (about the same as Caesar did).

Over time, spy cars became more and more intricate and original. In the Middle Ages, various devices were actively invented by the Inquisition, in the Age of Enlightenment and in the New Age - pundits. The purpose of their inventions, such as the Jefferson cipher, was far from military affairs. Although many developments subsequently found their application in encryption machines of intelligence in many countries of the world.

PUZZLES AND PUZZLES

The appearance of the Enigma cipher machine.

The heyday of various mechanical encoders / decoders falls on the era of the greatest wars in terms of scope - at the beginning of the 20th century. The development of such machines was carried out with varying success in Europe (primarily in England and Germany), and in the United States, and in Soviet Russia. The most popular was Enigma - the development of German engineers.

The machine is not named after the name of its inventor - there is such a word, which means "mystery" in translation. And Arthur Sherbius invented and patented this machine. At different times, four options were developed and patented, but none received commercial success due to the high cost. Sherbius did not give up and went to work in an office that bought a patent for an invention from him. Arthur did not live to see the triumph of his offspring. Several years passed before the efforts of Enigma engineers did not arouse the interest of various structures. First of all, the officers of the Reichswehr became interested in her. Die is cast…

Modifications

The scheme of the Enigma encryption machine.

Through the efforts of Wehrmacht specialists, Enigma was constantly improved and went through several modifications: A, B, C, etc. One of the simplest options - modification B - was a kind of electric typewriter. It consisted of a combination of mechanical and electrical systems. The mechanical part is a QWERTY keyboard layout, a set of rotating rotors located along the shaft. The rotors were set in motion by a stepped mechanism when a particular key was pressed. The specific mechanism of work from modification to modification could vary, but in general terms it was the same.

The mechanical parts of the unit moved, forming a changing electrical circuit. That is, the encryption of letters was carried out electrically. Each time the key was pressed, the rightmost rotor moved one position, and under certain conditions other rotors moved as well. Their movements led to various cryptographic transformations with each subsequent keystroke on the keyboard. The constant change in the electrical circuit due to the rotation of the rotors made it possible to implement a polyalphabetic substitution cipher. For example, the pin for the letter E could be connected to the pin for the letter T on the other side of the rotor. But when using several rotors in a bunch (3-4), due to their constant movement, encryption turned out to be more reliable.

For every tricky cipher there is always ...

"Peace to all!" - said Winston Churchill and threw the best minds of Great Britain to decipher the Enigma code.

Noticing the encryption activity of Germany, potential adversaries took up countermeasures. For example, in Poland they started with the theoretical foundations of machine cryptology and slowly practiced decryption. After the unconditional defeat of Poland, France took the lead in these endeavors. Which, as we remember, was also occupied. Therefore, the cunning British acted as successors and achieved good results in deciphering. They started with detailed cryptological and mathematical analysis. For this, both the encryptions themselves and ready-made decrypted texts were needed. At the next stage, the British connected a whole army of experts in various fields: linguistics, mathematics, mechanics - in total, according to various sources, up to 10,000 people. The whole painstaking process of work was personally supervised by Winston Churchill, who realized the importance of this kind of work as early as 1914.

The decryption process went much faster when Alan Turing joined the encryption team. He created a model of analysis, called the "Turing machine". Alan was the first to guess to carefully listen to the encrypted morning weather reports. They necessarily contained the word "weather" (Wetter), which stood in a strictly defined place in the sentence, according to the rules of German grammar. In addition, many factors played into the hands of cryptologists: the mistakes of German operators, the seizure of Enigma copies and cipher books ... In a word, from the beginning of the summer of 1940, the British deciphered all messages transmitted using Enigma. It is believed that without such a success, the Second World War could have lasted a couple of years longer. Although it is possible that the British exaggerate their contribution. A typewriter is a typewriter, and no one has yet canceled the significance of the Second Front ...

Rice. 3.1. The appearance of the Enigma cipher machine

Enigma ( Enigma) is a portable cipher machine used to encrypt and decrypt secret messages. More precisely, Enigma is a whole family of electromechanical rotary machines that have been used since the 1920s.

Enigma was used for commercial purposes, as well as in military and government services in many countries of the world, but it was most widely used in Germany during the Second World War. It is the Enigma of the Wehrmacht (Wehrmacht Enigma)- the German military model - is most often the subject of study.

Although the Enigma cipher was, from a cryptographic point of view, rather weak, in practice only the combination of this factor with others, such as operator errors, procedural flaws, and seizures of Enigma copies and codebooks, allowed English cryptanalysts to open messages encrypted with the Enigma cipher.

Rice. 3.2. Electrical diagram of Enigma (replacing the letter "A" with the letter "D" in the text)

The enciphering action of Enigma is shown for two successively pressed keys - the current flows through the rotors, "reflects" from the reflector, then returns through the rotors again. The gray lines in the figure show other possible electrical circuits within each rotor. The letter "A" is replaced in the ciphertext in different ways by successive keystrokes, first to "G", then to "C". The signal takes a different route due to the rotation of the rotor.

Like other rotary machines, Enigma consisted of a combination of mechanical and electrical systems. The mechanical part included a keyboard, a set of rotating disks (rotors) along the shaft, and a stepped mechanism that sets one or more rotors in motion with each keystroke. The movement of the rotors results in different character substitution options for each next keystroke on the keyboard.

The mechanical parts moved, forming a changing electrical circuit - that is, in fact, encryption was carried out electrically. When the keys were pressed, the circuit was closed, the current passed through the various components and eventually turned on one of the many light bulbs that displayed the displayed letter. For example, when encrypting a message beginning with “ANX...”, the operator first pressed the “A” button, and the “Z” light turned on, that is, “Z” became the first letter of the cryptogram. The operator continued encryption by pressing “N” on the keyboard and so on until the end of the original message.

The constant change in the electrical circuit through which the current flowed, due to the rotation of the rotors, made it possible to implement a polyalphabetic substitution cipher, which gave high resistance for that time.

Rotors

Rice. 3.3. Left side of the Enigma rotor, flat electrical contacts visible

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Rice. 3.4. Right side of rotor, pins visible

Rotors are the heart of Enigma. Each rotor is a disk approximately 10 cm in diameter, made of hard rubber or Bakelite, with spring-loaded pins on one side of the rotor arranged in a circle; on the other side there is a corresponding number of flat electrical contacts. Pin and flat contacts correspond to letters in the alphabet; usually it is 26 letters "A" ... "Z". When in contact, the contacts of adjacent rotors close the electrical circuit. Inside the rotor, each pin is connected to some flat one. The connection order may vary.

By itself, the rotor reproduces the encryption by simply replacing characters. For example, the pin for the letter "E" can be connected to the pin for the letter "T" on the other side of the rotor. But when using several rotors in a bundle (usually three or four), due to their constant movement, a more stable type of polyalphabetic encryption is obtained.

The rotor can take one of 26 positions in the machine. It can be rotated by hand using a knurled finger wheel that protrudes outwards as shown in Fig. 3.5. So that the operator can always determine the position of the rotor, each rim has an alphabetical ring; one of the letters is visible through the window. In early models of the Enigma, the alphabetical ring was fixed; in later versions, a complicated design was introduced with the possibility of its adjustment. Each rotor contains a recess (or several recesses) used to control the movement of the rotors.

Rice. 3.5. Rotor disassembled

1. notched ring
2. marking dot for contact "A"
3. alphabet ring
4. tinned contacts
5. wiring
6. pin contacts
7. spring lever for ring adjustment
8. sleeve
9. finger ring
10. ratchet wheel

Rice. 3.6. Three rotors connected in series

Military versions of the Enigma were produced with multiple rotors; the first model contained only three. In 1938 there were five of them, but only three of them were used in the car at the same time. These types of rotors were marked with Roman numerals I, II, III, IV, V, all with one notch located at different places in the alphabet ring. In naval versions Wehrmacht Enigma contained more rotors than the others: six, seven or eight.

AT Wehrmacht Enigma each rotor is attached to an adjustable notched ring. The five basic rotors (I-V) had one notch each, while the naval ones with additional rotors (VI-VIII) had two. At some point, the notch hits against the pawl, allowing it to engage the next rotor's ratchet on the next keystroke. When the pawl does not fall into the recess, it simply slides over the surface of the ring without catching the gears. In a single notch system, the second rotor advances one position while the first advances 26. Similarly, the third rotor advances one step while the second advances 26 steps. The peculiarity was that the second rotor also turned if the third turned; this means that the second rotor could turn twice with two successive keystrokes, the so-called "two-step movement", which leads to a decrease in the encryption period.

Rice. 3.7. Enigma rotors assembled. Three movable rotors are placed between two fixed parts: the entrance ring and the reflector (labeled "B" on the left)

Input wheel

Input wheel ( Eintrittswalze in German), or the input stator, connects the plugboard, or (in its absence) the keyboard and lampboard, to the rotors. Although the fixed connection of wires is of comparatively little importance in terms of security, it proved to be a bit of an obstacle in the work of the Polish cryptanalyst Marian Redzewski when he tried to determine the way the wires were switched inside the rotors. The commercial version of Enigma connected the letters in the order they appeared on the keyboard: QA, WB, EC, and so on. However, the military version connected them in direct alphabetical order: AA, BB, CC, etc.

Reflector

With the exception of early models A and B, the last rotor was followed by a reflector ( Umkehrwalze in German), a patented detail that distinguished the Enigma family from other rotary machines developed at the time. The reflector connects the contacts of the last rotor in pairs, switching the current through the rotors in the opposite direction, but along a different route. The reflector guarantees that the transformation implemented by Enigma is an involution, i.e. the decryption process is symmetrical to the encryption process. In addition, the reflector gives Enigma the property that no letter can be encrypted by itself. This was a serious conceptual flaw, subsequently exploited by decryptors.

Based on the materials of the dissertation "Ciphering machines and devices for decryption during the Second World War", defended at the University of Chemnitz (Germany) in 2004.

Introduction. For the general public, the word "Enigma" (Greek for riddle) is synonymous with the concepts of "cipher machine" and "code breaking", which is taken care of by submarine films and similar novels that have little to do with reality. Little is known about the fact that there were other cipher machines, for which special decryption machines were created to "break", and about the consequences that this had in the Second World War, little is known about this to the general public.

And no wonder: there is too little information about this in popular publications. And the information available there is usually either insufficient or unreliable. This is all the more regrettable, because the breaking of encryption codes was of exceptionally important historical significance for the course of the war, since the allies (in the anti-Hitler coalition), thanks to the information obtained in this way, had significant advantages, they were able to compensate for some of the omissions of the first half of the war and were able to make optimal use of their resources in the second half of the war. According to Anglo-American historians, if it were not for the breaking of German encryption codes, the war would have lasted two years longer, additional victims would have been required, it is also possible that an atomic bomb would have been dropped on Germany.

But we will not deal with this issue, but will limit ourselves to scientific, technical and organizational circumstances that contributed to the disclosure of German encryption codes. And what is especially important, how and why it was possible to develop machine methods of “hacking” and successfully use them.
Breaking the Enigma codes and the codes of other cipher machines provided the Allies with access not only to military-tactical information, but also to information from the Foreign Ministry, police, SS and railway. This also includes messages from the Axis countries, especially Japanese diplomacy, and the Italian army. The Allies also received information about the internal situation in Germany and its allies.

Thousands of Secret Service teams worked on deciphering the codes in England alone. This work was personally supervised by the Prime Minister of England, Winston Churchill, who knew about the importance of this work from the experience of the First World War, when he was the Secretary of the Navy of the British government. Already in November 1914, he ordered to decipher all intercepted enemy telegrams. He also ordered the previously intercepted telegrams to be deciphered in order to understand the mindset of the German command. This is a testament to his foresight. The most famous result of this activity of his is forcing the entry of the United States into the First World War.
Equally far-sighted was the creation of English listening stations - then it was a completely new idea - especially listening to the radio traffic of enemy ships.

Even then and in the period between the two world wars, Churchill equated such activities with a new type of weapon. Finally, it was clear that it was necessary to classify their own radio communications. And all this had to be kept secret from the enemy. There are great doubts that the leaders of the Third Reich were aware of all this. In the leadership of the Wehrmacht (OKW) there was a department with a small number of cryptologists and with the task of "developing methods for disclosing enemy radio messages", and it was about front-line radio reconnaissance officers who were charged with providing front-line commanders with tactical information on their sector of the front. In the German army, the encryption machines used were not evaluated by cryptologists (in terms of encryption quality and hacking capabilities), but by technical specialists.

The Allies followed the gradual improvement of German encryption technology and also improved the methods of breaking encryption codes. The facts that testified to the awareness of the allies, the Germans attributed to betrayal and espionage. In addition, in the Third Reich, there was often no clear subordination, and the encryption services of different branches of the military not only did not interact with each other, but also hid their skills from cryptographers of other branches of the military, since “competition” was in the order of things. The Germans did not try to unravel the encryption codes of the allies, since they had few cryptologists for this, and those that were, worked in isolation from each other. The experience of British cryptologists showed that the joint work of a large team of cryptologists made it possible to solve almost all the tasks. Towards the end of the war, a gradual transition began in the field of encryption from machine-based work to computer-based work.

Cipher machines in military affairs were first used in Germany in 1926. This prompted potential adversaries of Germany to join in the development of their own methods of encryption and decryption. For example, Poland took up this issue, and at first she had to develop the theoretical foundations of machine cryptology, since "manual" methods were not suitable for this. A future war would require thousands of radio messages to be deciphered daily. It was Polish specialists who in 1930 were the first to start work on machine cryptological analysis. After the outbreak of war and the occupation of Poland and France, these works were continued by British specialists. The theoretical work of the mathematician A. Turing was especially important here. Beginning in 1942, the disclosure of encryption codes became extremely important, as the German command increasingly used radio communications to transmit their orders. It was necessary to develop completely new ways of cryptological analysis for decryption machines.

History reference.
Julius Caesar was the first to use text encryption. In the 9th century, the Arab scholar Al-Kindi first considered the problem of deciphering a text. The works of Italian mathematicians of the 15th-16th centuries were devoted to the development of encryption methods. The first mechanical device was invented in 1786 by a Swedish diplomat, and such a device was at the disposal of the American President Jefferson in 1795. It was only in 1922 that this device was improved by the US Army cryptologist Mowborn. It was used to encrypt tactical messages until the outbreak of World War II. Patents to improve usability (but not encryption security) have been issued by the US Patent Office since 1915. All this was supposed to be used to encrypt business correspondence. Despite numerous improvements in devices, it was clear that only short texts were encrypted.

At the end of the First World War and in the first years after it, there are several inventions created by amateurs for whom it was a kind of hobby. Let's name two of them: Hebern (Hebern) and Vernam (Vernam), both Americans, neither of them, most likely, heard about the science of cryptology at all. The last of the two even implemented some operations of Boolean logic, which at that time very few people knew about, except for professional mathematicians. Professional cryptologists took up further improvement of these encryption machines, which made it possible to increase their security against hacking.

Since 1919 German designers also begin to patent their developments, one of the first was the future inventor of Enigma Arthur Scherbius (1878 - 1929). Four variants of similarly designed machines were developed, but there was no commercial interest in them, probably because the machines were expensive and difficult to maintain. Neither the Navy nor the Foreign Ministry accepted the proposals of the inventor, so he tried to offer his encryption machine to the civilian sectors of the economy. The army and the Foreign Ministry continued to use book encryption.

Arthur Scherbius went to work for a firm that bought his patent for a cipher machine. This firm continued to improve Enigma even after the death of its author. In the second version (Enigma B), the machine was a modified electric typewriter, on one side it had an encryption device in the form of 4 interchangeable rotors. The firm advertised the machine widely and advertised it as unbreakable. The officers of the Reichswehr became interested in her. The fact is that in 1923 Churchill's memoirs were published, in which he spoke about his cryptological successes. This caused shock among the leadership of the German army. German officers found out that most of their military and diplomatic communications had been deciphered by British and French experts! And that this success was largely determined by the weakness of the amateurish encryption invented by amateur cryptographers, since military German cryptology simply did not exist. Naturally, they began to look for reliable ways to encrypt military messages. Therefore, they developed an interest in Enigma.

Enigma had several modifications: A, B, C, etc. Modification C could perform both encryption and decryption of messages; she did not require complex maintenance. But its products were not yet resistant to hacking, because the creators were not advised by professional cryptologists. It was used by the German Navy from 1926 to 1934. The next modification of Enigma D was also a commercial success. Subsequently, since 1940, it was used in railway transport in the occupied regions of Eastern Europe.
In 1934 in the German navy began to use the next modification of the Enigma I.

It is curious that Polish cryptologists tried to decipher German radio messages classified by this machine, and the results of this work became somehow known to German intelligence. At first, the Poles were successful, but the German intelligence “watching” them informed their cryptologists about this, and they changed the ciphers. When it turned out that Polish cryptologists could not crack Enigma-1 encrypted messages, this machine was also used by the ground forces - the Wehrmacht. After some improvement, it was this cipher machine that became the main one in the Second World War. Since 1942, the German submarine fleet has adopted the Enigma-4 modification.

Gradually, by July 1944, control over the encryption business was transferred from the hands of the Wehrmacht to the roof of the SS, the main role here was played by the competition between these branches of the armed forces. From the very first days of WWII, the armies of the USA, Sweden, Finland, Norway, Italy and other countries are saturated with encryption machines. In Germany, machine designs are constantly being improved. The main difficulty in this was caused by the inability to find out whether the enemy is able to decipher the texts encrypted by this machine. Enigma of various modifications was introduced at levels above the division, it continued to be produced after the war (model "Schlüsselkasten 43") in Chemnitz: in October 1945. 1,000 pieces were produced, in January 1946. - Already 10,000 pieces!

Telegraph, historical reference.
The advent of electric current caused the rapid development of telegraphy, which, not by chance, took place in the 19th century in parallel with industrialization. The driving force was the railways, which used the telegraph for the needs of railway traffic, for which all kinds of devices such as pointers were developed. In 1836, the Steinhel device appeared, and in 1840 it was developed by Samuel Morse (Samuel MORSE). Further improvements came down to the Siemens and Halske printing telegraph (Siemens & Halske, 1850), which converted received electrical impulses into readable type. And invented in 1855. Hughes, the printing wheel, after a series of improvements, served well into the 20th century.

The next important invention to speed up the transfer of information was created in 1867 by Wheatstone: punched tape with Morse code, which the device felt mechanically. The further development of telegraphy was hampered by the insufficient use of the bandwidth of the wires. The first attempt was made by Meyer (B.Meyer) in 1871, but it failed because it was prevented by different length and number of impulses in Morse letters. But in 1874, the French engineer Emile Baudot managed to solve this problem. This solution became the standard for the next 100 years. The Bodo method had two important features. First, it became the first step towards the use of binary calculus. And secondly, it was the first reliable multi-channel data transmission system.

The further development of telegraphy rested on the need to deliver telegrams with the help of postmen. A different organizational system was required, which would include: a device in each house, servicing it by special personnel, receiving telegrams without the help of personnel, constant inclusion in the line, issuing texts page by page. Such a device would only have prospects of success in the United States. In Europe, until 1929, the postal monopoly prevented the appearance of any private device for transmitting messages, they had to be only at the post office.

The first step in this direction was taken in 1901 by the Australian Donald Murray. He, in particular, modified the Baudot code. This modification was the standard until 1931. He did not have commercial success, since he did not dare to patent his invention in the United States. Two American inventors competed in the USA: Howard Krum and E.E. Kleinschmidt. Subsequently, they united in one firm in Chicago, which began to produce equipment in 1024, which enjoyed commercial success. Several of their machines were imported by the German firm Lorenz, installed in post offices and obtained a license to produce them in Germany. Since 1929, the postal monopoly in Germany has been abolished, and private individuals have access to telegraph channels. The introduction in 1931 of international standards for telegraph channels made it possible to organize telegraph communications with the whole world. The same devices began to be produced since 1927 by Siemens and Halske.

For the first time, the 27-year-old American Gilbert Vernam, an employee of ATT, managed to combine the telegraph with a cipher machine. In 1918 he applied for a patent in which he empirically used Boolean algebra (of which, by the way, he had no idea and which was then being studied by several mathematicians around the world).
A great contribution to cryptology was made by the American officer William Friedman, who made American cipher machines practically unbreakable.

When Siemens and Halske telegraph machines appeared in Germany, the German navy became interested in them. But his leadership was still under the impression that the British during the First World War had cracked the German codes and read their messages. Therefore, they demanded that the telegraph apparatus be connected to the cipher machine. This was then a completely new idea, because encryption in Germany was done manually and only then the ciphertexts were transmitted.

In the USA, this requirement was met by Vernam devices. In Germany, this work was undertaken by Siemens and Halske. They filed their first open patent on this topic in July 1930. By 1932 a workable apparatus was created, which at first was freely sold, but since 1934. was classified. Since 1936 these devices began to be used in aviation, and since 1941. - and ground troops. Since 1942 began machine encryption of radio messages.

The Germans continued to improve various models of encryption machines, but in the first place they put the improvement of the mechanical part, referring to cryptology in an amateurish way, manufacturing firms did not involve professional cryptologists for consultations. Of great importance for all these problems were the works of the American mathematician Claude Shannon, who has been well-read since 1942. worked at Bell Labs and conducted secret mathematical research there. Even before the war, he was famous for proving the analogy between Boolean algebra and relay connections in telephony. It was he who discovered the "bit" as a unit of information. After the war, in 1948 Shannon wrote his main work "The Mathematical Theory of Communications". After that, he became a professor of mathematics at the university.

Shannon was the first to consider the mathematical model of cryptology and developed the analysis of ciphertexts by information-theoretical methods. The fundamental question of his theory is: "How much information does the encrypted text contain compared to the clear text?" In 1949, he published The Theory of Communications of Secret Systems, in which he answered this question. The analysis carried out there was the first and only one to quantify the reliability of the encryption method. Analysis after the war showed that neither German nor Japanese cipher machines were unbreakable. In addition, there are other sources of information (for example, intelligence) that greatly simplify the task of deciphering.

The position of England forced her to exchange long ciphertexts with the United States, it was the great length that made their decipherment possible. In a special department of the British secret service M 16, a method was developed that increased the degree of secrecy of the message - ROCKEX. The American method of encryption for the Ministry of Foreign Affairs was hacked by German specialists and the corresponding messages were decrypted. Upon learning of this, the United States in 1944. replaced an imperfect system with a more reliable one. Around the same time, the German Wehrmacht, the Navy and the Foreign Ministry also changed the encryption technique to a newly developed one. Soviet encryption methods were also not very reliable, because of which they were hacked by American services and many Soviet intelligence officers who were spying on the American atomic bomb were identified (Operation Venona - breaking).

Breaking.
Now let's talk about HACKING German cipher machines by the British, that is, machine guessing the way texts are encrypted in them. . This work received the English name ULTRA. Non-machine decryption methods were too laborious and unacceptable in war conditions. How were the English deciphering machines arranged, without which the Allies could not have gained an advantage over the German cryptographers? What information and textual material did they need? And was there a mistake by the Germans here, and if so, why did it happen?

First, the scientific and technical foundations.
First, preliminary scientific work was carried out, since it was necessary, first of all, to analyze the algorithms cryptologically and mathematically. This was possible because ciphers were widely used by the German Wehrmacht. Such an analysis required not only ciphertexts obtained by eavesdropping, but also plaintexts obtained by espionage or theft. In addition, different texts were needed, encrypted in the same way. At the same time, a linguistic analysis of the language of the military and diplomats was carried out. With long texts, it became possible to mathematically establish the algorithm even for an unfamiliar cipher machine. Then it was possible to reconstruct the car.

For this work, the British brought together approximately 10,000 people, including mathematicians, engineers, linguists, translators, military experts, and other employees to sort data, verify and archive it, and maintain machines. This association was called BP (Bletchley Park - Bletchley Park), it was personally controlled by Churchill. The information obtained turned out to be a powerful weapon in the hands of the allies.

How did the British take possession of the Wehrmacht Enigma? Poland was the first to decipher the German codes. After the First World War, it was in constant military danger from both of its neighbors - Germany and the USSR, who dreamed of regaining the lands lost and transferred to Poland. In order not to face surprises, the Poles recorded radio messages and deciphered them. They were greatly alarmed by the fact that after the introduction in February 1926. in the German Navy Enigma C, as well as after its introduction in the ground forces in July 1928. they could not decipher messages encrypted by this machine.

Then the BS4 department of the Polish General Staff suggested that the Germans had machine encryption, especially since the early commercial versions of Enigma were known to them. Polish intelligence confirmed that in the Wehrmacht from June 1, 1930. Enigma 1 is used. Poland's military experts failed to decipher the German messages. Even having obtained documents for Enigma through their agents, they could not succeed. They concluded that there was a lack of scientific knowledge. Then they instructed three mathematicians, one of whom studied in Göttingen, to create a system of analysis. All three received additional training at the University of Poznań and were fluent in German. They managed to reproduce the Enigma device and create a copy of it in Warsaw. We note the outstanding achievements in this of one of them, the Polish mathematician M. Reevsky (1905 - 1980). Although the Wehrmacht was constantly improving the encryption of its messages, Polish specialists were able to do so until January 1, 1939. decrypt them. After that, the Poles began to cooperate with the allies, to whom they had not reported anything before. Such cooperation, in view of the obvious military danger, was already expedient. July 25, 1939 they gave the British and French representatives all the information they knew. On August 16 of the same year, the Polish "gift" reached England, and English experts from the newly created VR decryption center began to work with it.

British cryptologists after the First World War were reduced, they remained only under the roof of the Foreign Office. During the war in Spain, the Germans used Enigma D, and the English cryptologists who remained in the service, under the guidance of the eminent philologist Alfred Dillwyn (1885-1943), continued to work on deciphering German messages. But purely mathematical methods were not enough. By this time, at the end of 1938. Alan Turing, a mathematician from Cambridge, was among the attendees of the English courses for the training of cryptographers. He took part in the attacks on Enigma 1. He created an analysis model known as the "Turing machine", which made it possible to assert that the decryption algorithm necessarily exists, it only remained to open it!

Turing was included in the BP as a conscript. By May 1, 1940. he made serious progress: he took advantage of the fact that every day at 6 o'clock in the morning the German weather service transmitted an encrypted weather forecast. It is clear that it necessarily contained the word "weather" (Wetter), and that the strict rules of German grammar predetermined its exact position in the sentence. This allowed him to eventually come to a solution to the problem of cracking the Enigma, and he created an electromechanical device for this. The idea came to him at the beginning of 1940, and in May of the same year, with the help of a group of engineers, such a device was created. The task of deciphering was facilitated by the fact that the language of German radio messages was simple, expressions and individual words were often repeated. German officers did not know the basics of cryptology, considering it insignificant.

The British military, and especially Churchill personally, demanded constant attention to the decoding of messages. Since the summer of 1940 the British deciphered all messages encrypted with Enigma. Nevertheless, British specialists were constantly improving the deciphering technique. By the end of the war, British decoders had 211 deciphering devices operating around the clock. They were served by 265 mechanics, and 1675 women were involved in the duty. The work of the creators of these machines was appreciated many years later when they tried to recreate one of them: due to the lack of necessary personnel at that time, the work on recreating the famous machine continued for several years and remained unfinished!

The instruction for the creation of decrypting devices, created then by Dühring, was banned until 1996 ... Among the means of decryption was the method of "forced" information: for example, British planes destroyed the pier in the port of Calle, knowing that a message from the German services would follow about this with a set known to the British in advance words! In addition, the German services transmitted this message many times, each time encoding it in different ciphers, but word for word ...

Finally, the most important front for England was the submarine war, where the Germans used a new modification of the Enigma M3. The English fleet was able to remove such a machine from a German submarine they had captured. On February 1, 1942, the German Navy switched to using the M4 model. But some German messages, encrypted in the old way, erroneously contained information about the design features of this new machine. This greatly facilitated the task of Turing's team. Already in December 1942. Enigma M4 was hacked. December 13, 1942 the British Admiralty received accurate data on the location of 12 German submarines in the Atlantic ...

According to Turing, in order to speed up decryption, it was necessary to switch to the use of electronics, since electromechanical relay devices did not perform this procedure quickly enough. On November 7, 1942, Turing went to the United States, where, together with a team from Bell Laboratories, he created an apparatus for top-secret negotiations between Churchill and Roosevelt. At the same time, under his leadership, American decryption machines were improved, so that the Enigma M4 was broken completely and provided the British and Americans with comprehensive intelligence information until the end of the war. Only in November 1944 did the German command have doubts about the reliability of their encryption technology, but this did not lead to any measures ...

(Translator's note: since, starting from 1943, the Soviet intelligence officer Kim Philby was at the head of the British counterintelligence, then all the information immediately entered the USSR! Some of this information was transmitted to the Soviet Union both officially through the British Bureau in Moscow and semi-officially through Alexander Rado, the Soviet resident in Switzerland.)

Chiffriermaschinen und Entzifferungsgeräte
im Zweiten Weltkrieg:
Technikgeschichte und informatikhistorische Aspekte
Von der Philosophischen Fakultät der Technischen Universität Chemnitz genehmigte
Dissertation
zur Erlangung des academischen Grades doctor philosophiae (Dr. phil.)
von Dipl.-Ing.Michael Pröse