Who deciphered the Enigma code? Turing was able
The development of the Enigma family of encryption machines started immediately after the First World War, back in 1918. The German Arthur Scherbius received a patent for a rotary encryption machine, which, in fact, was the first version of the “Riddle” (as Enigma is translated from German). In 1923, Scherbius, together with a partner, organized an enterprise with the difficult-to-pronounce name Chiffriermaschinen Aktiengesellschaft, which established the serial production of encryption devices.
The first two Enigma models, A and B, were moderately successful. The real breakthrough in 1925 was the Model C - with a reflector, much more compact than its predecessors. Enigma C weighed only 12 kg with dimensions of 28 by 34 by 15 cm, while previous models weighed about 50 kg, with dimensions of 65 by 45 by 35 centimeters. Model C almost immediately began to be used on ships of the German fleet.
Enigma S. Image: Crypto Museum
In 1928, military specialists commissioned by the Wehrmacht redesigned the design of civilian encryption machines, constructing the Enigma-G model, which two years later was modified into the Enigma-I version. It was this 1930 device that became the basis for many versions that were used by a variety of military services during World War II. There were Enigma variants with a number of rotors from 3 to 8. However, the eight-rotor version, created specifically for higher army structures, was quickly taken out of service due to unreliability.
"Drain" that did not turn into hacking
Although Enigma was praised by the highest ranks of the German army for its effectiveness and reliability, the secrecy of the messages encrypted on it was soon threatened. The reason for this was agent Asche - aka Hans-Tilo Schmidt, an employee of the encryption bureau of the German Ministry of Defense since 1931 - an agent of French intelligence. Schmidt handed over obsolete codes to the French, which he was obliged to destroy, and also “leaked” instructions for using a military version of the encryption machine.
Sheet with Enigma encryption codes. Photo: Telenet
French intelligence reacted rather coolly to the information of “agent Ashe”. Having your own agent in the camp of a potential enemy was useful, but Enigma was considered such a reliable machine that they didn’t even try to break it in France.. But in Poland, to which the French transferred materials from their German agent, there were cryptographic geniuses who figured out the code.
"Polish Turing"
The Reliable Machine was hacked by Marian Rejewski, a 27-year-old mathematician who completed secret courses in cryptography. Although he did not work alone in the Polish Cipher Bureau, only Rejewski was entrusted with working on decrypting Enigma I. Marian immediately began actively looking for vulnerabilities in the message key, selecting the first six letters from the daily ciphergrams and compiling correspondence tables.
First, he managed to discover 4 repeating sequences of letters in the ciphers. And then, thanks to the information that Enigma has only three reels, and the initial setting consists of three letters of the Latin alphabet, Rejewski established the number of possible code chains. It turned out to be many times smaller than previously expected: 3! 263 against 26!. This made it possible to compile a complete catalog of all chains within a year.
Thanks to Reevsky, it became clear that the number of code chains is 3,824,262,831,196,002,461,538 times less than previously assumed.
Marian Rejewski. Photo: Poland
Apparently, having realized that their ciphers could be read, German cryptographers began to change the configuration of the machine’s rotors much more often. And in the fall of 1938, the encryption principle was changed, which made it impossible to recognize ciphergrams based on previous methods. However, Reevsky and his colleagues saw through this trick, which consisted of the so-called key doubling and was, in fact, a cryptographic error.
Within a few months, the Poles created a device called the “Rejewski Bomb”, so named either for the characteristic ticking sound when working, or in honor of the round cakes that Marian loved very much. The device searched by pattern, taking into account that the pairs of the first and fourth, second and fifth, third and sixth letters of the cipher text corresponded to the same letters of the unciphered text.
Rejewski's cryptological "bomb". 1 - rotors for selecting keys, 2 - motor for rotating the rotors, 3 - indicator stand indicating successful selection of the code. Image: Ministerstwo Edukacji Narodowej
It was the work of Marian Rejewski that became the basis for Alan Turing's success. Although it cannot be said that the Briton merely appropriated someone else’s success. Yes, in 1939, during the attack of the Third Reich troops, the Poles transferred all the work of local codebreakers to British intelligence agents. But by this time Reevsky’s technique was useless for working with Enigma.
Chasing mistakes and trying options
Already in December 1938, two more rotors were added to the machine’s three rotors, and the number of possible rotor positions increased 10 times. Instead of 6 “Rejewski bombs”, the Poles even then needed 60 decryption devices. And in May 1940, the Germans abandoned the idea of doubling the key, and the very concept of the Polish decryption machine turned out to be useless. So Turing did a huge amount of work to solve the improved “Riddle” - especially since Polish cryptanalysts destroyed the “bombs” in September 1939, after German troops invaded the country.
An error occurred while loading.The working principle of the Turing machineRejewski was a genius, but he made a mistake by constantly looking for the mistakes of others. The Polish codebreaker's method was to identify Enigma vulnerabilities. But the Germans themselves constantly improved their machine, forcing the young mathematician to constantly be in a catching-up position.
The British were no longer suitable for the “Rejewski bomb”, which used an exhaustive search of all possible combinations to select a key.
Turing proposed a simpler and less labor-intensive method of decryption: take into account in your work that part of the source text is known. Despite the ingenuity of the German code, despite all the precautions, German soldiers most often communicated with each other in short, stereotypical phrases that could be “recognized.” The exact place of individual phrases in the encryption could be determined by mechanically enumerating 26 letters of the Latin alphabet. An additional relief was that in the Enigma cipher, none of the letters of the original message were encoded with the same letter.
"Bomb" for the Third Reich
Based on this technique, Turing Bombs were developed. The first was launched on March 18, 1940 - for each possible initial position of the rotors, it performed a comparison with a known fragment of text and formed logical assumptions. If inconsistencies were found in these assumptions, the option was “rejected.” Thus, from a huge variety of options - 10 19 possible combinations for the usual version of Enigma or 10 22 for the version used by submariners - only a few logically consistent ones remained, on the basis of which the machine selected the cipher. The team of decryptors worked around the clock, in several shifts a luxurious mansion called Bletchley Park in the town of Milton Keynes, 72 km from London. Employees processed thousands of messages daily, highlighting so-called clues in the ciphergrams - greetings, numbers, repeating pieces of text. Based on these fragments, the machine made its assumptions.
Sometimes it happened that the information was not enough to solve the code. This was especially critical on the eve of major German operations. Back then, British troops resorted to a technique called gardening. To do this, the British Navy carried out demonstrative mining of certain areas of the sea, and in Bletchley Park they then determined a known text based on enemy reports on mine clearance.
A genius appreciated too late
Turing did everything to ensure that England did not surrender under the onslaught of the German fleet and aviation, and the USSR had not only America as its allies. As one of Alan’s colleagues once said: “I don’t presume to say that we won the war thanks to Turing. However, without him they could have lost it.”
Alan Turing is considered one of the most important figures in the history of cryptography. But his work on deciphering Enigma hardly influenced the development of this science - no matter how strange it may sound. All decryption machines from Bletchley Park were destroyed after World War II, and the very fact of decryption attempts - successful and not so successful - was kept secret until the 1970s. Already in 1952, the scientist himself turned from an unknown hero into an object of public shame: Turing was accused of homosexuality and forced to undergo a course of hormonal therapy, from which the “Enigma winner” fell into deep depression and committed suicide two years later.
In 2009, Alan Turing was recognized as "one of the UK's most famous victims of homophobia". In 2013, Britain's Queen Elizabeth II formally pardoned Turing, who was accused of "obscenity."
And yet: today the name Turing is familiar to most people. The Turing Completeness Principle, the Turing Test, the Turing Machine, and one of the most prestigious awards in computer science are named after the genius. In the movies, Alan was played by the terribly fashionable Benedict Cumberbatch, and a monument to him was erected in Manchester.
Almost at any time of the year, the English countryside looks the same: green meadows, cows, medieval-looking houses and a wide sky - sometimes gray, sometimes dazzling blue. It was just transitioning from the first mode to the more rare second mode when the commuter train rushed me to Bletchley station. It’s hard to imagine that surrounded by these picturesque hills, the foundations of computer science and cryptography were laid. However, the upcoming walk through the most interesting museum dispelled all possible doubts.
Such a picturesque place, of course, was not chosen by the British by chance: inconspicuous barracks with green roofs, located in a remote village, were just what was needed to hide a top-secret military facility where they were constantly working on breaking the codes of the Axis countries. Bletchley Park may not look impressive from the outside, but the work that was done here helped turn the tide of the war.
Crypto hacks
In wartime, people entered Bletchley Park through the main gate by presenting a security pass, but now they buy a ticket at the entrance. I stayed there a little longer to look at the adjacent souvenir shop and temporary exhibition dedicated to First World War intelligence technologies (by the way, also an interesting topic). But the main thing lay ahead.
Bletchley Park itself is about twenty long one-story buildings, which in English are called hut, and in Russian are usually translated as “house”. I silently called them “huts,” combining one with the other. In addition to them, there is a mansion (aka Mansion), where the command worked and distinguished guests were received, as well as several auxiliary buildings: former stables, a garage, residential buildings for staff.
Those same houses The estate in all its glory Inside the estate looks richer than the hutsEach house has its own number, and these numbers have historical significance; you will definitely find them in any story about Bletchley Park. In the sixth, for example, intercepted messages were received, in the eighth they were engaged in cryptanalysis (Alan Turing worked there), in the eleventh there were computers - “bombs”. The fourth house was later allocated for work on the version of Enigma that was used in the navy, the seventh - for the Japanese variation on the Enigma theme and other ciphers, in the fifth they analyzed transmissions intercepted in Italy, Spain and Portugal, as well as German police encryption. And so on.
You can visit the houses in any order. The furnishings in most of them are very similar: old furniture, old things, tattered notebooks, posters and maps from the Second World War. All this, of course, did not lie here for eighty years: the houses were first transferred from one state organization to another, then they were abandoned, and only in 2014 did restorers meticulously restore them, saving them from demolition and turning them into a museum.
This, as is customary in England, was approached not only carefully, but also with imagination: in many rooms, the voices of actors and sounds are heard from hidden speakers, which create the impression that work is in full swing around. You walk in and hear the clatter of a typewriter, someone's footsteps and a radio in the distance, and then you "overhear" someone's animated conversation about a recently intercepted encryption.
But the real curiosity is the projections. For example, this man, who seemed to be sitting at the table, greeted me and briefly told me about the local customs.
Many rooms are kept in twilight so that the projections can be seen betterThe most interesting thing, of course, was to look at Alan Turing's desk. His office is located in house eight and looks very modest.
This is what Alan Turing's desk looked likeWell, you can look at Turing’s creation itself - the Enigma deciphering machine - in house number 11 - in the same place where the very first model of the “bomb” was assembled at one time.
Cryptological bomb
This may be news to you, but Alan Turing was not the first to decrypt Enigma using brute force. His work is preceded by research by Polish cryptographer Marian Rejewski. By the way, it was he who called the decryption machine a “bomb.”
The Polish “bomb” was much simpler. Note the rotors on topWhy "bomb"? There are several different versions. For example, according to one, this was supposedly the name of a variety of ice cream beloved by Rejewski and his colleagues, which was sold in a cafe not far from the encryption bureau of the Polish General Staff, and they borrowed this name. A much simpler explanation is that in Polish the word "bomb" can be used to make an exclamation like "eureka!" Well, a very simple option: the car was ticking like a bomb.
Shortly before the capture of Poland by Germany, Polish engineers handed over to the British all the developments related to decoding German ciphers, including drawings of the “bomb”, as well as a working copy of Enigma - not a German, but a Polish clone, which they managed to develop before the invasion. The rest of the Poles' developments were destroyed so that Hitler's intelligence would not suspect anything.
The problem was that the Polish version of the “bomb” was designed only for the Enigma I machine with three fixed rotors. Even before the start of the war, the Germans introduced improved versions of Enigma, where the rotors were replaced every day. This made the Polish version completely unusable.
If you've seen The Imitation Game, you're already quite familiar with the setting at Bletchley Park. However, the director could not resist and made several digressions from real historical events. In particular, Turing did not create the prototype of the “bomb” with his own hands and never called it “Christopher”.
Popular English actor Cryptocode Podbirac as Alan Turing
Based on the Polish machine and the theoretical work of Alan Turing, engineers at the British Tabulating Machine Company created the “bombs” that were supplied to Bletchley Park and other secret facilities. By the end of the war, there were already 210 vehicles, but with the end of hostilities, all “bombs” were destroyed by order of Winston Churchill.
Why did the British authorities need to destroy such a wonderful data center? The fact is that the “bomb” is not a universal computer - it is intended exclusively for decoding messages encrypted by Enigma. As soon as this was no longer needed, the machines also became unnecessary, and their components could be sold off.
Another reason may have been the premonition that the Soviet Union would not be Britain's best friend in the future. What if the USSR (or anywhere else) began to use technology similar to Enigma? Then it is better not to demonstrate to anyone the ability to break its ciphers quickly and automatically.
Only two "bombs" survived from wartime - they were transferred to GCHQ, the UK Government Communications Center (think of it as the modern equivalent of Bletchley Park). They say they were dismantled in the sixties. But GCHQ graciously agreed to provide the museum at Bletchley with old drawings of the “bombs” - alas, not in the best condition and not entirely. Nevertheless, enthusiasts managed to restore them, and then create several reconstructions. They are now in the museum.
It’s interesting that during the war, the production of the first “bomb” took about twelve months, but the reconstructors from the BCS Computer Conservation Society, starting in 1994, worked for about twelve years. Which, of course, is not surprising, given that they had no resources other than their savings and garages.
How did Enigma work?
So, “bombs” were used to decrypt messages that were obtained after encryption with Enigma. But how exactly does she do this? Of course, we will not analyze its electromechanical circuit in detail, but it is interesting to know the general principle of operation. At least, it was interesting for me to listen and write down this story from the words of a museum employee.
The design of the “bomb” is largely determined by the design of the Enigma itself. Actually, we can consider that a “bomb” is several dozen “Enigmas” put together in such a way as to sort out the possible settings of the encryption machine.
The simplest Enigma is a three-rotor one. It was widely used by the Wehrmacht, and its design meant that it could be used by the average soldier, not a mathematician or engineer. It works very simply: if the operator presses, say, P, a light will light up under one of the letters on the panel, for example under the letter Q. All that remains is to convert it into Morse code and transmit it.
An important point: if you press P again, there is a very small chance of getting Q again. Because every time you press the button, the rotor moves one position and changes the configuration of the electrical circuit. Such a cipher is called polyalphabetic.
Look at the three rotors at the top. If you, for example, enter Q on the keyboard, then Q will first be replaced by Y, then by S, by N, then reflected (it turns out K), changed again three times and the output will be U. Thus, Q will be encoded as U. But what if I type U? It turns out Q! This means the cipher is symmetric. This was very convenient for military applications: if two places had Enigmas with the same settings, messages could be freely transmitted between them.
This scheme, however, has a big drawback: when entering the letter Q, due to the reflection at the end, under no circumstances could it be obtained Q. German engineers knew about this feature, but did not attach much importance to it, but the British found an opportunity to exploit it . How did the British know about the insides of the Enigma? The fact is that it was based on a completely unsecret development. The first patent for it was filed in 1919 and described a machine for banks and financial institutions that allowed the exchange of encrypted messages. It was sold on the open market, and British intelligence managed to purchase several copies. By their example, by the way, the British Typex encryption machine was made, in which the defect described above was corrected.
The very first Typex model. As many as five rotors!The standard Enigma had three rotors, but in total you could choose from five options and install each of them in any slot. This is exactly what is reflected in the second column - the numbers of the rotors in the order in which they are supposed to be installed in the machine. Thus, already at this stage it was possible to obtain sixty settings options. Next to each rotor there is a ring with letters of the alphabet (in some versions of the machine - the corresponding numbers). The settings for these rings are in the third column. The widest column is an invention of German cryptographers, which was not in the original Enigma. Here are the settings that are set using the plug panel by connecting letters in pairs. This confuses the whole scheme and turns it into a difficult puzzle. If you look at the bottom line of our table (the first day of the month), the settings will be as follows: rotors III, I and IV are placed in the machine from left to right, the rings next to them are set at 18, 24 and 15, and then the letters N are connected on the panel with plugs and P, J and V and so on. Taking all these factors into account, there are about 107,458,687,327,300,000,000,000 possible combinations - more than seconds have passed since the Big Bang. It is not surprising that the Germans considered this car extremely reliable.
There were many variants of Enigma, in particular, a variant with four rotors was used on submarines.
Hacking Enigma
Breaking the code, as usual, was made possible by the unreliability of people, their mistakes and predictability.
The Enigma manual says to select three of the five rotors. Each of the three horizontal sections of the “bomb” can check one possible position, that is, one machine can simultaneously run three out of sixty possible combinations. To check everything, you need either twenty “bombs” or twenty consecutive checks.
However, the Germans made a pleasant surprise for the English cryptographers. They introduced a rule according to which the same position of the rotors should not be repeated for a month, or for two days in a row. This sounds like it was supposed to improve reliability, but in reality it had the opposite effect. It turned out that by the end of the month the number of combinations that needed to be checked was significantly reduced.
The second thing that helped in decryption was traffic analysis. The British had been listening to and recording encrypted messages from Hitler's army since the beginning of the war. There was no talk of decryption at that time, but sometimes the fact of communication itself is important, plus such characteristics as the frequency at which the message was transmitted, its length, time of day, and so on. Also, using triangulation, it was possible to determine where the message was sent from.
A good example is the transmissions that came from the North Sea every day from the same locations, at the same time, on the same frequency. What could it be? It turned out that these were meteorological ships that reported daily weather data. What words might be contained in such a transmission? Of course, “weather forecast”! Such guesses pave the way for a method that today we call a plaintext attack, but in those days we called “cribs.”
Since we know that Enigma never outputs the same letters as the original message, we need to sequentially match the "hint" with each substring of the same length and see if there are any matches. If not, then this is a candidate string. For example, if we check the hint “weather in the Bay of Biscay” (Wettervorhersage Biskaya), we first write it opposite the encrypted string.
Q F Z W R W I V T Y R E * S* X B F O G K U H Q B A I S E Z W E T T E R V O R H E R * S* A G E B I S K A Y A |
We see that the letter S is encrypted into itself. This means that the hint needs to be shifted by one character and checked again. In this case, several letters will match at once - move them again. R matches. We move twice more until we come across a potentially correct substring.
If we were dealing with a substitution cipher, then we could end there. But since this is a polyalphabetic cipher, we need settings and initial positions of the Enigma rotors. They were the ones who were picked up with the help of “bombs”. To do this, pairs of letters must first be numbered.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 R W I V T Y R E S X B F O G K U H Q B A I S E W E T T E R V O R H E R S A G E B I S K A Y A |
And then, based on this table, create a so-called “menu” - a diagram that shows which letter of the original message (that is, “hints”) is supposedly encrypted into which letter and in what position. The “bomb” is set up according to this scheme.
Each of the reels can take one of 26 positions - one for each letter of the alphabet. Behind each of the reels there are 26 contacts, which are connected in thick cables in such a way that the machine searches for settings on the plug panel that give sequential matches of the letters of the encrypted string with the hint.
Since the structure of the “bomb” does not take into account the switching device inside the Enigma, it produces several options during operation that the operator must check. Some of them will not work simply because in Enigma you can only connect one plug to one socket. If the settings are not suitable, the operator starts the machine again to get the next option. In about fifteen minutes, the “bomb” will go through all the options for the selected reel position. If it is guessed correctly, then all that remains is to select the settings of the rings - without automation (we won’t go into details). Then, on English Typex machines modified to be compatible with Enigma, the encryption was translated into clear text.
Thus, operating with a whole fleet of “bombs”, by the end of the war, the British received up-to-date settings every day even before breakfast. In total, the Germans had about fifty channels, many of which broadcast much more interesting things than the weather forecast.
Allowed to touch with hands
At the Bletchley Park Museum you can not only look around, but also touch the decipherment with your own hands. Including using touchscreen tables. Each of them gives his own task. In this, for example, it is proposed to combine Banburi sheets (Banburismus). This is an early method of deciphering Enigma, which was used before the creation of “bombs”. Alas, it was impossible to decipher something in this way during the day, and at midnight all successes turned into a pumpkin due to the next change in settings.
Dummy “data center” in Hut 11
What is in house number 11, where there used to be a “server room”, if all the “bombs” were destroyed in the last century? To be honest, I still deep down hoped to come here and find everything in the same form as before. Alas, no, but the hall is still not empty.
Here are these iron structures with plywood sheets. On some there are life-size photographs of “bombs”, on others there are quotes from the stories of those who worked here. They were mostly women, including from the WAF, the women's service of the Royal Air Force. The quote in the picture tells us that switching cables and looking after the “bombs” was not an easy task at all, but an exhausting daily work. By the way, another series of projections is hidden between the dummies. The girl tells her friend that she had no idea where she would serve, and is completely amazed by what is happening at Bletchley. Well, I was also amazed by the unusual exhibit!
I spent a total of five hours at Bletchley Park. This was barely enough to get a good look at the central part and a glimpse of everything else. It was so interesting that I didn’t even notice how time passed until my legs began to ache and ask to go back - if not to the hotel, then at least to the train.
And besides the houses, dimly lit offices, restored “bombs” and long stands with accompanying texts, there was something to see. I have already mentioned the hall dedicated to espionage during the First World War, there was also a hall about the decryption of Lorenz and the creation of the Colossus computer. By the way, in the museum I discovered the “Colossus” itself, or rather the part that the reenactors managed to build.
For the most resilient, a small museum of computer history awaits outside Bletchley Park, where you can get acquainted with how computer technology developed after Turing. I also looked there, but walked quickly. I've already seen enough of BBC Micro and Spectrum in other places - you can do this, for example, at the Chaos Constructions festival in St. Petersburg. But you won’t find a living “bomb” anywhere.
Based on materials from the dissertation “Encryption machines and decryption devices during the Second World War,” defended at the University of Chemnitz (Germany) in 2004.
Introduction. For the general public, the word “Enigma” (in Greek - a riddle) is synonymous with the concepts of “cipher machine” and “code breaking”, which has been taken care of by films about submarines and similar novels that have little to do with reality. Little is known to the general public about the fact that there were other encryption machines, for which special decryption machines were created to “break”, and about the consequences that this had in the Second World War.
And not surprisingly: 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 extremely 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 omissions of the first half of the war and were able to optimally use their resources in the second half of the war. According to Anglo-American historians, if it had not been for the breaking of German encryption codes, the war would have lasted two years longer, additional casualties would have been required, and 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 the scientific, technical and organizational circumstances that contributed to the disclosure of German encryption codes. And what is especially important is how and why it was possible to develop machine methods of “hacking” and use them successfully.
Hacking the Enigma codes and the codes of other encryption 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 reports 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.
In England alone, a secret service team of thousands worked to decipher the codes. 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 the deciphering of all intercepted enemy telegrams. He also ordered that previously intercepted telegrams be deciphered in order to understand the thinking of the German command. This is evidence of his foresight. The most famous result of this activity was forcing the US entry into the First World War.
Equally far-sighted was the creation of English listening stations - then 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 our 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 realized 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 revealing enemy radio messages,” and we were talking 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 assessed not by cryptologists (in terms of encryption quality and cracking capabilities), but by technical specialists.
The Allies followed the gradual improvement of German encryption technology and also improved methods of breaking encryption codes. The Germans attributed facts indicating the awareness of the Allies 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 the cryptographers of other branches of the military, since “competition” was the order of the day. The Germans did not try to unravel the Allied encryption codes, since they had few cryptologists for this, and those that they had worked in isolation from each other. The experience of English cryptologists has shown that the joint work of a large team of cryptologists made it possible to solve almost all the tasks assigned. Towards the end of the war, a gradual transition in the field of encryption began from machine-based work to computer-based work.
Encryption machines in military affairs were first used in Germany in 1926. This prompted Germany's potential adversaries to develop their own encryption and decryption methods. For example, Poland took up this issue, and first it 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 every day. It was Polish specialists who were the first to begin work on machine cryptological analysis in 1930. After the outbreak of war and the occupation of Poland and France, this work was continued by English specialists. The theoretical work of the mathematician A. Turing was especially important here. Beginning in 1942, breaking encryption codes became extremely important, as the German command increasingly used radio communications to transmit its orders. It was necessary to develop completely new methods of cryptological analysis for decryption machines.
Historical reference.
Julius Caesar was the first to use text encryption. In the 9th century, the Arab scholar Al-Kindi first considered the problem of text decipherment. The work of Italian mathematicians of the 15th and 16th centuries was devoted to the development of encryption methods. The first mechanical device was invented in 1786 by a Swedish diplomat; such a device was also at the disposal of the American President Jefferson in 1795. Only in 1922 this device was improved by the American army cryptologist Mauborn. It was used to encrypt tactical messages until the outbreak of World War II. Patents for improving usability (but not for encryption security) were issued by the US Patent Office starting in 1915. All this was supposed to be used to encrypt business correspondence. Despite numerous improvements in devices, it was clear that only short text encryption was reliable.
At the end of the First World War and in the first years after it, several inventions appeared, created by amateurs for whom this was a kind of hobby. Let's name two of them: Hebern and Vernam, both Americans, neither of them, most likely, had ever heard of the science of cryptology. The latter of the two even implemented some operations of Boolean logic, which at that time few people knew about except professional mathematicians. Professional cryptologists began further improving these encryption machines, which made it possible to increase their security against hacking.
Since 1919 German designers also began to patent their developments; one of the first was the future inventor of the Enigma, Arthur Scherbius (1878 - 1929). Four variants of similar 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 Ministry of Foreign Affairs accepted the inventor's proposals, so he tried to offer his encryption machine to the civilian sectors of the economy. The army and the Foreign Ministry continued to use encryption using books.
Arthur Scherbius went to work for the company that bought his patent for an encryption machine. This company 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 was equipped with an encryption device in the form of 4 replaceable rotors. The company widely displayed the machine and advertised it as unhackable. Reichswehr officers became interested in her. The fact is that in 1923, Churchill’s memoirs were published, in which he talked about his cryptological successes. This caused shock among the leadership of the German army. German officers learned 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 amateurish encryption, invented by amateur cryptologists, since German military cryptology simply did not exist. Naturally, they began to look for strong encryption methods for military communications. Therefore, they became interested in Enigma.
Enigma had several modifications: A, B, C, etc. Modification C could perform both encryption and decryption of messages; it 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, Enigma D, was also a commercial success. Subsequently, since 1940, it was used in railway transport in the occupied areas of Eastern Europe.
In 1934 The German navy began to use another modification of Enigma I.
It is curious that Polish cryptologists tried to decrypt German radio messages classified by this machine, and the results of this work somehow became known to German intelligence. At first, the Poles were successful, but the German intelligence “watching” them reported this to their cryptologists, and they changed the codes. When it turned out that Polish cryptologists were unable to crack messages encrypted with Enigma -1, the ground forces, the Wehrmacht, also began to use this machine. After some improvement, it was this encryption machine that became the main one in the Second World War. Since 1942, the German submarine fleet adopted the Enigma-4 modification.
Gradually, by July 1944, control over the encryption business passed from the hands of the Wehrmacht to the roof of the SS, the main role here was played by 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 were saturated with encryption machines. In Germany, machine designs are constantly being improved. The main difficulty in this case was caused by the inability to find out whether the enemy was able to decipher texts encrypted by a given 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 information.
The advent of electric current caused the rapid development of telegraphy, which, not coincidentally, occurred 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. Steinhel's device appeared in 1836, and in 1840 it was developed by Samuel MORSE. Further improvements came in the form of the Siemens and Halske printing telegraph (Siemens & Halske, 1850), which converted received electrical impulses into readable type. And invented in 1855. The printing wheel, after a number of improvements, was still used by Hughes in the 20th century.
The next important invention for accelerating 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 insufficient use of wire capacity. The first attempt was made by B. Meyer in 1871, but it failed because the different lengths and number of pulses in Morse letters prevented it. But in 1874, the French engineer Emile Baudot managed to solve this problem. This solution became the standard for the next 100 years. Baudot's method had two important features. Firstly, it was 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 using postmen. A different organizational system was required, which would include: a device in every house, its maintenance by special personnel, receiving telegrams without the help of staff, constant connection to the line, issuing texts page by page. Such a device would have prospects of success only in the USA. In Europe, until 1929, the postal monopoly prevented the appearance of any private device for transmitting messages; they had to be installed only at the post office.
The first step in this direction was taken in 1901 by the Australian Donald Murray. In particular, he modified Baudot's 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 USA. In the USA, two American inventors competed with each other: Howard Krum and E.E. Kleinschmidt. Subsequently, they merged into one company in Chicago, which began producing equipment in 1024, which enjoyed commercial success. The German company Lorenz imported several of their machines, installed them in post offices and obtained a license for their production in Germany. Since 1929, the postal monopoly in Germany was abolished, and private individuals gained access to telegraph channels. The introduction of international standards for telegraph channels in 1931 made it possible to organize telegraph communications with the whole world. The same devices began to be produced in 1927 by Siemens and Halske.
The first person to combine a telegraph with an encryption machine was 27-year-old American Gilbert Vernam, an employee of the ATT company. In 1918 he applied for a patent in which he empirically used Boolean algebra (which, by the way, he had no idea about and which was then being studied by several mathematicians around the world).
The American officer William Friedman made a great contribution to cryptology; he made American encryption machines virtually unbreakable.
When telegraph devices from Siemens and Halske appeared in Germany, the German Navy became interested in them. But its leadership was still under the impression that the British had cracked the German codes and read their messages during the First World War. Therefore, they demanded to connect the telegraph apparatus with a encryption machine. This was a completely new idea at that time, because encryption in Germany was done manually and only then the encrypted texts were transmitted.
In the USA, this requirement was met by Vernam devices. In Germany, the company Siemens and Halske took on this work. They filed the first open patent on this topic in July 1930. By 1932 a workable device 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 forces. Since 1942 Machine encryption of radio messages began.
The Germans continued to improve various models of encryption machines, but they put the improvement of the mechanical part in the first place, treating cryptology in an amateurish manner; manufacturing companies did not involve professional cryptologists for consultations. Of great importance for all these problems were the works of the American mathematician Claude Shannon, who was well-read since 1942. worked at Bell Laboratories 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 this 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 encrypted texts using information theoretical methods. The fundamental question of his theory is: “How much information does ciphertext contain compared to plaintext?” In 1949, he published the work “The Theory of Communications of Secret Systems,” in which he answered this question. The analysis carried out there was the first and only to quantify the strength of an encryption method. Post-war analysis showed that neither German nor Japanese encryption machines were unbreakable. In addition, there are other sources of information (for example, intelligence) that greatly simplify the decryption task.
England's position forced it to exchange long cipher texts with the United States; it was the great length that made deciphering them 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 encryption method for the Foreign Office was broken by German experts and the corresponding messages were decrypted. Having learned about this, the United States in 1944. replaced an imperfect system with a more reliable one. Around the same time, the German Wehrmacht, Navy and Foreign Ministry also exchanged encryption technology for newly developed ones. Soviet encryption methods were also insufficiently reliable, which is why they were hacked by American services and many Soviet intelligence officers involved in espionage for the American atomic bomb were identified (Operation Venona - breaking).
Breaking into.
Now let's talk about the British HACKING German encryption machines, that is, the machine unraveling of the method of encrypting texts in them. . This work received the English name ULTRA. Non-machine decryption methods were too labor-intensive and unacceptable in war conditions. How were the English deciphering machines constructed, without which the Allies could not have achieved an advantage over the German codebreakers? What information and textual material did they need? And was there a German mistake here, and if so, why did it happen?
First, the scientific and technical basics.
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 encryption was widely used by the German Wehrmacht. Such analysis required not only ciphertexts obtained through eavesdropping, but also plaintexts obtained through 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. Given long texts, it became possible to mathematically establish an algorithm even for an unfamiliar cipher machine. Then they managed 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 the data, check it, archive it, and maintain the machines. This association was called BP (Bletchley Park) and was under the personal control of Churchill. The information received turned out to be a powerful weapon in the hands of the Allies.
How did the British master the Wehrmacht Enigma? Poland was the first to decipher 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. To avoid surprises, the Poles recorded radio messages and deciphered them. They were greatly alarmed 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 were unable to decipher messages encrypted by this machine.
Then the BS4 department of the Polish General Staff assumed that the Germans had acquired machine encryption, especially since they knew the early commercial versions of Enigma. Polish intelligence confirmed that in the Wehrmacht from June 1, 1930. Enigma 1 is used. Polish military experts were unable to decipher German messages. Even having received Enigma documents through their agents, they could not achieve success. They concluded that there was a lack of scientific knowledge. Then they commissioned three mathematicians, one of whom studied in Göttingen, to create a system of analysis. All three received additional training at the University of Poznan and spoke fluent German. They managed to reproduce the Enigma device and create a copy of it in Warsaw. Let us note the outstanding achievements of one of them, the Polish mathematician M. Rejewski (1905 - 1980). Although the Wehrmacht constantly improved the encryption of its messages, Polish specialists succeeded until January 1, 1939. decipher them. After this, the Poles began to cooperate with the allies, to whom they had not previously communicated anything. Such cooperation was already advisable in view of the obvious military danger. July 25, 1939 they conveyed to the English 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 BP Decoding Center began working with it.
British cryptologists were reduced after the First World War, remaining only under the roof of the Foreign Office. During the war in Spain, the Germans used Enigma D, and the remaining English cryptologists, under the leadership of the outstanding 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. Cambridge mathematician Alan Turing was among the visitors to the English cryptographer training courses. 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 a decryption algorithm definitely exists, all that remained was to discover it!
Thüring was included in the BP as a person liable for military service. By May 1, 1940 he achieved serious success: 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 "wetter" (Wetter), and that the strict rules of German grammar determined its exact position in the sentence. This allowed him to ultimately come to a solution to the problem of breaking the Enigma, and he created an electromechanical device for this. The idea came to him in early 1940, and in May of the same year, with the help of a group of engineers, such a device was created. The task of decoding was made easier 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 unimportant.
The British military, and especially Churchill personally, demanded constant attention to deciphering messages. Since the summer of 1940 The British deciphered all messages encrypted using Enigma. Nevertheless, English specialists were constantly improving decryption technology. By the end of the war, British codebreakers had 211 decryption devices working around the clock. They were served by 265 mechanics, and 1,675 women were brought on 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 lasted several years and remained unfinished!
The instructions for creating decryption devices created by Dühring at that time were 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 in advance that the German services would report this with a set of information known in advance to the British words! In addition, German services transmitted this message many times, each time encoding it with different codes, 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 British fleet was able to remove such a vehicle from a captured German submarine. On February 1, 1942, the German Navy switched to using the M4 model. But some German messages, encrypted in the old way, mistakenly contained information about the design features of this new machine. This made the task much easier for Thuring's team. Already in December 1942. Enigma M4 was cracked. On December 13, 1942, the British Admiralty received precise data on the location of 12 German submarines in the Atlantic...
According to Turing, 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 Enigma M4 was finally cracked and until the end of the war it provided the British and Americans with comprehensive intelligence information. 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 head of British counterintelligence was the Soviet intelligence officer Kim Philby, all information immediately came to the USSR! Some of this information was transmitted to the Soviet Union both officially through the British bureau in Moscow, and also semi-officially through the Soviet resident in Switzerland, Alexander Rado.)
Chiffriermaschinen und Entzifferungsgeräte
im Zweiten Weltkrieg:
Technikgeschichte und informatikhistorische Aspekte
Von der Philosophischen Fakultät der Technischen Universität Chemnitz genehmigte
Dissertation
zur Erlangung des akademischen Grades doctor philosophiae (Dr.phil.)
von Dipl.-Ing.Michael Pröse
The legendary Enigma encryption machine has become a symbol of spy stories during the Second World War. According to various estimates, hacking it shortened the war by two years and saved millions of lives. This is the story of how Britain's best cryptanalysts, armed with mathematical tools, were able to decipher the most complex German code.
The birth of a legend
Cryptanalysis- the science of methods for deciphering encrypted information without using the original key. Cryptographers, on the contrary, are engaged in encrypting texts and other data.
Paradoxically, the Enigma encryption machine was not created for the military, but to classify business negotiations. The device was developed and patented in 1918 by a German engineer. Arthur Sherbius. The first series of Enigma weighed more than 50 kg. Due to the high cost and complexity of use, the encryption machine did not initially attract the attention of buyers. For five years, Scherbius managed to sell only a few copies for the needs of foreign armies and communications companies.
Arthur Sherbius
Inventor of the Enigma encryption machine, which means “riddle” in Greek. In 1908 he graduated from the University of Hanover, and ten years later he organized the private company Scherbius and Ritter, which produced Enigma. The inventor did not live to see the triumph of his brainchild - he died in 1929 as a result of an accident.
The encryption machine was highly appreciated by the German army. In 1925, it was adopted first by the Navy (model Funkschlussen C), and in 1930 by the Wehrmacht (Enigma I). The total number of encryptors produced before and during World War II exceeded 100 thousand. They were used by all types of armed forces of Nazi Germany, as well as military intelligence and security services.
Enigma ciphers
The operator encrypted the message using a code book. The entries in it looked like this:
We see installations on the 31st day of the month (the code changed every day). The operator must select reflector B, set the letters C, T and R on the rotors IV, I, VII, respectively. The following is the procedure for closing the contacts on the cross-panel. When encrypting, the operators followed the general rules: there are no spaces, punctuation marks are indicated by symbols (for example, a comma is YY, and quotation marks are X). In addition to the day code, each message had its own key (the position of the rotors), which was sent in encrypted form along with the text of the message.
What was this car? The design is based on 3 rotating drums (disks) with 26 electrical contacts on each - according to the number of letters of the Latin alphabet. With these contacts, the drums came into contact with each other and ensured the passage of an electrical impulse. Letters were applied to the ends of the contacts. Before starting work, the operator set a code word on all three reels and typed text on the keyboard. Each disk was responsible for a basic encryption step - replacing one letter with another, for example, P with W. Three disks made the encryption logic much more complicated. Each key press caused an electrical impulse, which, passing through the drums, turned the first disk one step. After the first drum made a full revolution, the second came into play, then the third - it was like the operation of an electric meter.
The electrical signal, passing through the drums, entered the reflector of the encryption machine. It consisted of 13 conductors, which were pairs of contacts on the back of the third disk. The reflector sent an electrical signal back to the drums, but along a new path - this significantly complicated the encryption mechanics. Next, the electrical impulse lit one of the indicator lamps, which showed the letter of the encrypted text.
Encryption device M-94
On the first versions of Enigma, three people usually worked at once: one read the text, the second typed it on the keyboard, and the third read the text from the indicator lights and wrote down the encrypted message. The machine had one fundamental flaw - the inability to encrypt a letter through itself. That is, for example, L could be encrypted with any letter of the alphabet, except, in fact, L. Later, this became one of the most important clues that led to the breaking of the cipher.
How does Enigma work?
Rotary discs. The heart of Enigma is disks with 26 contacts on each side. The input and output contacts were connected randomly. Passing through the rotor, the signal was converted from one letter to another.
Reflector had 26 contacts and was connected to the third rotor. It “reflected” the current from the third rotor and sent it back, but along a different path. The reflector ensured that no letter would be encrypted through itself.
Display panel had 26 light bulbs and repeated the layout of a mechanical keyboard. It served as an indicator of the output letter during the encryption process.
Switch. Under the Enigma switch there was a compartment with a 4.5 volt battery.
Keyboard included 26 characters: from A to Z. It had no numbers, no commas, no spacebar. Punctuation marks were replaced by conventional symbols (for example, comma - YY). The numbers were written in words.
Cross panel. It was present in military models of Enigma and was a set of sockets for plugs. Served to swap the contacts of two letters whose plugs were currently connected.
Battle on the radio
Three people worked on the first versions of Enigma: one read the text, the second typed it on the keyboard, the third wrote down the encryption
Germany in the early 1930s was actively arming itself and preparing for war. Particular attention was paid to deep secrecy when transmitting information via radio channels. Therefore, all Enigmas worked under conditions of secrecy: for each session of the encryption machine there were day keys (a set of letters indicating the initial position of the rotors), identical for the transmitter and receiver machines. Each cryptographer had a special notebook with hundreds of keys for each broadcast. Before sending a message, the operator came up with a new key for this message and encrypted it. Let's say the day key is AOH. The operator and the recipient set AOH on their rotors. Next, the operator encrypts the key to the message twice. Let's say he chose the EIN key. As a result of entering the EINEIN key twice, XHTLOA was displayed in the cryptogram. Next, the text was typed, encrypted using the EIN key. The recipient of the message entered the first 6 letters and decrypted the key - the initial position of the rotors for this message.
The situation was complicated by the fact that the Germans encrypted no more than 250 characters at a time, and a few years later they added two more reels. This significantly increased the resistance of the ciphers to cracking. The senior command staff used Enigma II for some time, consisting of eight rotors at once. However, due to the complexity of the work and low reliability, it was soon abandoned.
Sometimes the Germans deliberately littered the radio space: “Enigma” sent incoherent, meaningless scraps of phrases onto the air. We can say that German signalmen used a spam attack for the first time. All these measures undoubtedly complicated the work of European intelligence services to decipher the codes of the Third Reich.
"Wolf Packs" Dönitz
The ruthless submarine war waged by Nazi Germany left little chance for the commercial and military ships of the USSR, Great Britain and the USA. The main means of communication for Kriegsmarine submarines was the naval version of Enigma. With its help, the leadership organized strike groups of submarines and directed them towards convoys with the aim of destruction. Such a “wolf pack” attacked ships exclusively in a group and pursued dozens of miles, sending several ships to the bottom. One of the inspirers of this tactic was the commander of the German submarine fleet, Karl Dönitz. With the deciphering of the Enigma codes, the British began to receive accurate information about the location of enemy ships and their intentions - luck turned away from the “wolf packs”.
Intercepting the radiogram was not enough to decipher the message. Intelligence services helped. At the end of the 20s, a Polish group of cryptanalysts received a commercial version of Enigma. This allowed us to get a general idea of the logic of the encryption machine. A few years later, French intelligence was able to obtain an operating manual for the latest military model. However, all this only helped to understand the principle of operation of the device - it was still impossible to decipher the messages.
The Art of Cryptanalysis
A classic decoding technique is frequency analysis. The idea is that the frequency of occurrence of a certain letter or even a syllable in a long text is the same in any language and cipher. This makes it quite easy to solve codes created by replacing letters in the text - just reverse substitution. Enigma-type rotary cipher machines were much more resistant to crypto-cracking because they reduced the number of repeating sequences, which made frequency analysis powerless. Nowadays, cryptanalysis is based on the enormous computing power of computers and is widely used by private corporations, intelligence agencies and hackers.
The luckiest ones at this stage were the Polish cryptanalysts. Having gained access to the entire array of European intelligence data, they were able to read German encryption from 1933 onwards. This lasted five years: in 1938, the Germans abandoned daytime keys and began to change the initial position of the rotor before each message. The operator sent the initial key, followed by the encrypted key for the given message. Thus, two factors of the system's vulnerability were eliminated: universal day keys for all radiograms and encryption of the message key twice (this practice, of course, helped codebreakers find patterns between letters).
In response to a new challenge, Poland created the “Bomb” - six interconnected Enigma machines that could, in a couple of hours, use brute force to calculate the initial key of radio encryption (the starting position of the reels). The deciphering machine received its unusual name for the characteristic ticking sound during operation, reminiscent of the sound of a clock mechanism. In fact, it was the prototype of a computer, in which cardboard punched cards were used as information storage media. The occupation of Poland in 1939 and the next complication of the Enigma design forced France and Great Britain to look for new ways of “hacking.”
The private estate of Bletchley Park in Buckinghamshire became the nerve center of the British intelligence services during the Second World War. It was here in 1939 that the most talented mathematicians and cryptanalysts gathered with one goal - to crack the Enigma code. The priority objectives of the program, called "Ultra", were the encryption of the German fleet - the Kriegsmarine, whose submarines sank many ships and sent cargo worth millions of pounds sterling to the bottom.
Alan Turing - Cambridge professor who managed to crack the Enigma code
From the very beginning of the research center known as Station X at Bletchley Park, a young professor from Cambridge stood out among the codebreakers. Alan Turing. He led the group that built the Bomba supercomputer using a Polish analogue. The machine processed thousands of German codes that were intercepted by British radios. In this gigantic volume of information, general patterns of the work of Enigma gradually began to emerge - the German radio operators turned out to be not without sin. Greetings, careless encoding of numbers, frequently repeated snippets of text - all these deviations from the encryption protocol were strictly taken into account in Station X. Over time, about 200 Bomb-type decryptors were built, which made it possible to process 3,000 German ciphers per day. By 1942, the Ultra scientific team was able to make significant progress towards the goal, but there were regular failures: the constant complications of Enigma and changes in work algorithms had an effect.
Turing's "bomb" consisted of 108 electromagnetic drums and weighed 2.5 tons
The British anti-submarine ship, which captured the German submarine U-559, provided invaluable assistance to the scientists. She had on board a complete and unharmed copy of Enigma with a complete set of documentation and a set of ciphers. British Prime Minister Winston Churchill spoke exhaustively about the significance of the Enigma decryption program: “It was thanks to Ultra that we won the war.”
Alan could have been born in India: his father Julius worked in the Indian Civil Service, and the family were just living in India when Ethel Sarah became pregnant. But the couple decided that it was better for the child to be born in London. Alan did just that.
From birth, Alan was, as they say, a strange child and at the same time a genius. According to some versions, he learned to read in just three weeks, and at the age of seven, Alan wanted to collect honey from wild bees during a picnic. To do this, he calculated the flight paths of insects among the heather and thus found the hive.
At the age of six, Alan Turing went to school, and at 13 he became a student at the famous private school Sherborne. It is curious that in Sherborne the humanities were much more valued, but Alan’s passion for mathematics was not encouraged. The school principal wrote to parents:
“I hope he won’t try to sit on two chairs at once. If he intends to remain in a private school, then he must strive to obtain an “education.” If he is going to be exclusively a “scientific specialist,” then a private school is a waste of time for him.”
There, in Sherborne, Alan met someone who became his close friend and, perhaps, his first love, Christopher Marcom. Unfortunately, the young man died from complications from bovine tuberculosis, leaving Alan in despair. It was this death that forced Turing to abandon his religious views and made him an atheist.
“I am sure that I will never meet again a companion so gifted and at the same time so charming,” Alan wrote to Marcom’s mother. “I shared with him my interest in astronomy (which he introduced me to), and he did the same for me... I know that I have to put as much energy, if not as much interest, into my work as I would have if I had he’s alive, that’s what he would like.”
Correspondence with his friend's mother continued for many years after Morcom's death, and all the letters were filled with tender memories of Christopher.
Alan entered King's College Cambridge, where his talents were already taken seriously. There he came up with the idea of a universal machine - it was still an abstract idea, from which the concept of a computer was later born. Alan studied mathematics and cryptography.
Bletchley Park, The Dilly Girls and The Turing Bomb
Bletchley Park was also called “Station X” or simply “BP” - it was a large mansion in the center of England, which during the Second World War was used for the needs of the main cryptographic department of Britain. Asa Briggs, a wartime historian and codebreaker, said: “Exceptional talent was needed at Bletchley, genius was needed. Turing was that genius."
Like any genius, he was strange. Colleagues called him by the short nickname Prof.
Historian Ronald Levin writes that Jack Goode, a cryptanalyst who worked with Turing, spoke of Alan as follows:
“In the first week of June every year he would have a bad attack of hay fever and would ride his bike to work wearing a gas mask to protect himself from the pollen. His bicycle was broken; the chain was falling off at regular intervals. Instead of fixing it, he counted the number of pedal revolutions through which the chain came off, got off the bike and manually adjusted it. Another time, he chained his mug to the radiator pipes to prevent it from being stolen.”
Because British men were at war, most of Bletchley's workers were women. Cryptographers worked long hours decoding intercepted messages.
“In 1939, the job of a codebreaker, although it required skill, was boring and monotonous,” says Andrew Hodges in The Universe of Alan Turing. “However, encryption was an integral attribute of radio communications. The latter was used in war in the air, at sea and on land, and a radio message for one became available to everyone, so the messages had to be rendered unrecognizable. They weren’t just made “secret,” like those of spies or smugglers, but the entire communication system was classified. This meant errors, limitations, and hours of work on each message. However, there was no choice."
One of the most famous teams was a group of women called the Dilly Girls. They worked under the direction of cryptanalyst Dilvin Knox. It was these women who deciphered the famous Enigma code, and Turing worked on the creation of a cryptanalytic machine. One of the "Dilly girls" was Joan Clarke.
Joan Clark
Turing became incredibly close to Joan, a rather reserved girl. She worked on deciphering maritime codes in real time, one of the most stressful jobs at Bletchley.
“We spent time together,” she recalled in a 1992 interview with BBC Horizon. “We went to the movies, but it was a big surprise for me when he said: “Will you agree to marry me?” I was surprised, but I didn’t doubt it for a second, I answered “yes,” and he knelt in front of my chair and kissed me even though we had no physical contact. The next day we went for a walk after lunch. And then he said that he had homosexual tendencies. Naturally, this worried me a little - I knew for sure that this would be forever.”
Turing broke off the engagement a few months later, but despite this they remained close friends.
Graham Moore, screenwriter of The Imitation Game, believes it was their strangeness that brought Alan and Joan together: “They were both outcasts and that was something they had in common, they saw things differently.”
Gross obscenity
In December 1951, 39-year-old Turing met Arnold Murray. He was 19. An unemployed handsome young man, thin, with big blue eyes and blond hair. Alan invited Arnold to a restaurant. After some time they saw each other again and spent the night together.
Although Alan tried to offer Arnold money, he said he didn't want to be treated like a prostitute. He "borrowed" money from Turing several times, and some time later someone robbed Alan's house.
Arnold confessed to his lover that his friend did it. Alan reported the robbery to the police, but he was forced to admit his homosexuality.
Alan was confident that parliament would soon legalize homosexual relations.
Arnold and Alan appeared in court. They were charged with “gross indecency” and both were found guilty. Arnold received parole, and Alan was given a choice: prison time or treatment for homosexuality with hormones.
Turing wrote to his friend Philip Hall: “I am given a suspended sentence for a year and am required to undergo treatment for the same period. The drugs are supposed to reduce sexual desire while it lasts... Psychiatrists seem to have decided that there is no use in getting involved with psychotherapy.”
And he also said: “Without a doubt, another person will come out of all this, but I don’t know who exactly.”
Poisoned Apple
On June 8, 1954, Turing's housekeeper found him dead in his room. Next to him lay a bitten apple, which most likely became the cause of death. Alan was very fond of Disney's Snow White. According to biographers Hodges and David Leavitt, he took "particularly acute pleasure in the scene where the Evil Queen plunges her apple into the poisonous drink."
Most likely, Alan poisoned the apple with cyanide and ate it.
In August 2009, British computer programmer John Graham-Cumming wrote a petition calling on the British government to apologize for persecuting Turing for his homosexuality. It collected more than 30,000 signatures, and Prime Minister Gordon Brown issued a statement of apology:
“Thousands of people have demanded justice for Alan Turing and demanded that he be treated appallingly. Turing was treated according to the law of that time, and we cannot turn back time, what they did to him was, of course, unfair. I and all of us deeply regret what happened to him. On behalf of the British Government and all those who live freely thanks to Alan's work, I say: Forgive us, you deserve better.
Photo: Getty Images, REX
