Enigma machine

GCHQ

by Richard Aldrich  · 10 Jun 2010  · 826pp  · 231,966 words

1920s, the German military adapted a Dutch invention to produce the Enigma cypher machine as an alternative to laborious hand cyphers. In fact, the first Enigma machines were sold commercially, and were widely used by banks and businesses. Enigma was what we now recognise as a ‘commercial off-the-shelf solution’ to

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a difficult military problem.15 The Enigma machine itself looked like an early typewriter in a square wooden box, but with a keyboard set out in alphabetical order rather than the traditional ‘QWERTY

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Knox, to Paris to meet their French and Polish opposite numbers. Eventually they discovered that the Poles had completely reconstructed the German version of the Enigma machine.17 Remarkably, by 1938 the Polish code-breakers were able to read the majority of German Army Enigma messages. The Polish breakthrough had been to

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six Enigma-type machines wired together to provide rapid processing of possible solutions. Polish resources were limited, and by late 1938 new advances in the Enigma machine were running ahead of the ability of the Poles to do their calculations. But the precious secrets that the Poles taught the British were enough

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1939. Before the Polish secret service was forced to flee Warsaw, its agents had achieved the remarkable feat of stealing several examples of the military Enigma machine from the German factory where they were made. In the late 1930s, Britain lived in the shadow of the aerial bomber. Following the tragic fate

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wrong. The Poles explained that the British had failed to think through the way in which the wiring was attached to the rotors of the Enigma machine. In early 1940, with this further helpful shove from its allies, Bletchley Park began breaking substantial amounts of Enigma traffic. There were many different Enigma

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lose it for a while, and quite often recovering it depended on second-guessing the lazy habits of the operators. German overconfidence in the improved Enigma machine led to basic mistakes that greatly simplified the task of those whose objective was to tease out the rotor setting for each day.31 By

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-breaking in the early years of the war was not just about the German military secrets revealed through Enigma. Even harder to break than the Enigma machine had been a German teleprinter on-line cypher machine known as ‘Tunny’, used by the German High Command to produce ‘Fish’ messages. On-line cypher

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of it dummy material, sometimes offering no obvious start or end points to each message. This went some way to eliminating another weakness of the Enigma machine – its operators, who were prone to human error. To address the problem of ‘Tunny’, the British later built ‘Colossus’, one of the earliest general-purpose

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in parallel, even though the Battle of the Atlantic gave Washington a legitimate need for Ultra intelligence. However, once the German Navy introduced an improved Enigma machine with four rotors, the British could not produce enough ‘bombes’ to deal with the increased number of tests required to break it.50 In September

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on their foray into Germany. No less important was the breaking of a number of Soviet military machine cyphers that were not dissimilar to the Enigma machine, or its widely used Swedish equivalent, the ‘Hagelin’ machine. GCHQ code-named these machines the ‘Poets Systems’. The first success was with an encoded Soviet

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-boggling complexity. Yet the British people were still not even aware of the wartime achievements of Bletchley Park. Ultra and its conquest of the German Enigma machine were still shrouded in government secrecy. Indeed, the official histories of the Second World War had been artfully constructed to hide code-breaking and deception

The Secrets of Station X: How the Bletchley Park codebreakers helped win the war

by Michael Smith  · 30 Oct 2011  · 440pp  · 109,150 words

War led a number of nations to adopt machine cyphers, which were seen as more difficult to break. The most famous of these was the Enigma machine. The first British contact with the machine came in 1921, when it was still in development. It was shown to the British military attaché in

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Berlin, in the hope of persuading the British armed forces to use it. The German Navy introduced the Enigma machine cypher in 1926 and for a brief period it remained a possibility that both the British and the German armed forces might use it. In

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oversaw the construction and security of British codes and cyphers, asked Hugh Foss, a specialist in machine cyphers, to test the commercially available machine. The Enigma machine resembled a small typewriter encased in a wooden box. It had a typewriter-style keyboard, set out in the continental QWERTZU manner, which differed slightly

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set number of times, the third wheel moved round one position. The point at which the next wheel moved was known as ‘the turnover’. The Enigma machine had two crucial features which Foss realised would help anyone trying to break it. A letter could not be encyphered as itself (so if the

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which British armed forces used with great success during the Second World War. A year after Foss’s investigation, the German Army began using the Enigma machine and within two years had introduced an enhancement that greatly improved its security. The Stecker-board was an old-fashioned telephone-style plugboard, which allowed

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cyphers with the Deuxième Bureau’s codebreaking operation since 1933. But it was not until late 1938 that the two sides began to discuss the Enigma machine in any detail. Given that the exchange on Russian material had been somewhat one-sided, with the British providing far more than they received in

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return, the French had a surprisingly large amount of material on the Enigma machine. Denniston wrote to Sinclair suggesting that the dialogue was worth continuing. The French had clearly not got far themselves but had produced some 100 documents

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, some of which were of more value than others. They included ‘photographs of documents relating to the use of the Enigma machine which did increase our knowledge of the machine and have greatly aided our researches’, Denniston said. Bertrand made clear that some of the French material

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French-German border, in late 1932, when Asche produced two operators’ manuals, one of which had a message which had been encyphered using a real Enigma machine, and a schedule of daily Army keys for September and October 1932. They were photographed by the French allowing Asche to return the documents to

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reason for seeking this liaison in the first place was the desire to leave no stone unturned which might lead to a solution of the Enigma Machine as used by various German services. This is of vital importance for us and the French have furnished us with documents which have assisted us

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problem for Knox was what he called ‘the QWERTZU’, by which he meant the way in which the letters on the keyboard of the Wehrmacht Enigma machines were wired to the letters on the wheels inside the machine, and he left the meeting in Paris none the wiser. One good thing did

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July 1939. It was only then that the Poles revealed the full extent of the progress they had made in reconstructing the Wehrmacht’s steckered Enigma machine. The Bureau Szyfrow had broken a number of German codes during the early 1920s but the introduction of Enigma had left them unable to read

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worked initially on a part-time basis and it was only in September 1932 that Rejewski, the best of the three, was given the steckered Enigma machine and asked to solve it. By the end of that year, assisted by Enigma key lists obtained by the French from Asche, he had reconstructed

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furious to discover that the Poles had got there first, sitting in ‘stony silence’ as they described their progress and produced a clone of the Enigma machine, reconstructed using the knowledge they had built up over the previous six years. But his good humour soon returned after they told him that the

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commonly used streams of text – known to the codebreakers as cribs – to narrow down the possibilities for the keys, settings and wheel orders of the Enigma machines. Turing enjoyed a good degree of progress on both. Menzies agreed funding of £100,000 for the construction of the first Bombes and the British

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. Machine cyphers like Enigma were developed to try to protect against these tell-tale frequencies and letter pairings, which is why the wheels of the Enigma machine were designed to move around one step after a number of key strokes. By doing this, the Germans hoped to ensure that no original letter

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opportunity to move the middle wheel on a notch. This reduced the odds to a more manageable proportion. They were shortened still further by the Enigma machine’s great drawback. No letter could ever be represented by itself. This was of great assistance in using cribs, pieces of plain text that were

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thought about how the system worked, and might be unravelled, Herivel tried to get into the mind of the operators who were setting up the Enigma machines. How did they go about it; what were they thinking when they did it? The operators using Enigma began each day by putting the correct

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, more than seven feet wide and two-and-a-half feet deep, containing a series of thirty rotating drums equating to the wheels of ten Enigma machines, although later versions simulated the action of twelve machines. It contained around ten miles of wire and about a million soldered connections. The Bombe was

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a possible match, it stopped and was quickly tested by the operator on a British Type-X cypher machine rigged up to work like an Enigma machine to see if it produced German text. If it did, the operator was able to declare: ‘The job’s up’ and pass it back for

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of the ‘Special Intelligence’. Denniston told Menzies that Currier and his colleagues had been ‘informed of the progress made on the Enigma machine’. The Americans were given ‘a paper model of the Enigma machine, detailing its internal wiring and how it worked, together with details of the Bombes. This was as much as, if

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the British, and doing nothing to assuage their concerns over US security, by writing an unclassified letter to demand that the Americans be given an Enigma Machine. Safford later claimed that the British reneged on their side of the deal and had ‘double-crossed us’. The US Navy sent the British all

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false perception that the British were holding back on the exchange deal, largely the result of the US Navy codebreakers, failure to understand the ‘paper Enigma machine’ the British had handed over, was to become endemic among a number of senior US Navy officers. Yet at the cutting edge, US codebreakers said

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out was by decyphering the messages passed between the Abwehr outstations in Paris, Madrid, Lisbon and their headquarters. But these links all used the Abwehr Enigma machine, which was completely different to those used by the other German services. Hut 6 had looked at the Abwehr Enigma early in 1941 but had

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were trusted or under suspicion, in which case steps could be taken to remedy the situation. Two months later, Mavis Lever solved a separate Abwehr Enigma machine, known as GGG, which was used near the Spanish border. By the spring of 1942, the information collected from the Bletchley Park decrypts had built

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given a chance to make the submarine cypher even more secure he jumped at it. The plan involved a slight internal re-design of the Enigma machine. A new, thinner reflector with different wiring was introduced, leaving space for an extra wheel that, while it did not rotate during encypherment, could be

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side of the U-Boat, causing so much damage that the commander was forced to surrender. Inside the U-Boat was the casing of an Enigma machine with a fourth indicator window. References to the fourth wheel soon started to appear in decyphered messages and, on occasions, operators used it in error

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Middlesex; increased recruitment of Wrens; and two different development programmes put in place to produce an upgraded Bombe that could cope with the four-wheel Enigma machine. Doc Keen began work on a high-speed machine with an additional row of wheels that could complete a standard three-wheel run in less

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‘U-Boat meetings’ with the Naval Section. He also increased pressure for the introduction of the new Bombes designed to cope with the four-wheel Enigma machine. But the solution to Shark was already in place. Two days after the Admiralty memorandum, a pinch of two German ‘short signal’ codebooks arrived at

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. Page 35 Germans begin using machine cyphers: Denniston, ‘The Government Code and Cypher School Between the Wars’, p.54. Page 36 Foss asked to test Enigma machine for British use: TNA PRO HW 25/10, H. R. Foss, Reminiscences on the Enigma, p.2. Pages 37–38 Working of Enigma and results

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QWERTZU: Michael Smith, Station X, Decoding Nazi Secrets, TV Books, New York, 1999, pp.30–31; Hinsley & Stripp, Codebreakers, p.127. Page 63 Delivery of Enigma machine to Menzies: Gustave Bertrand, ENIGMA ou La Plus Grande Enigmé de la Guerre 1939–45, Plon, Paris, 1973, p.60. Pages 64–8 Recruitment of

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.121. Page 87 Dryden memories: Hinsley & Stripp, Codebreakers, p.198. Pages 88–2 Turing: TNA PRO HW 25/3, A. M. Turing, Mathematical theory of ENIGMA Machine, p.136. Pages 89–3 Cillies: TNA PRO HW 43/70, History of Hut 6, pp.53–4; interviews with Susan Wenham and Mavis Batey

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, Joe 1, 2 Edward II, King 1 Eisenhower, Dwight 1, 2 el Alamein, Battle of 1 Elizabeth I, Queen 1 Elmer’s School 1, 2 Enigma machine used by German navy 1 offered to British armed forces 1, 2 description of 1 joint attempt by British and French to break 1 clones

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Flowers, Tommy 1, 2 Foley, Frank 1 Foreign Office takes control of GC&CS 1 Forster, Leonard 1 Fortitude South deception 1 Foss, Hugh and Enigma machine 1, 2 and liaison with Deuxième Bureau 1 description of 1 France, invasion of 1, 2, 3 Freeborn, Frederic 1 Freyberg, Bernard 1 Friendly, Alfred

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1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 Tolkien, J.R.R. 1 traffic analysis 1, 2 Travis, Edward 1 and Enigma machine 1 1 and Hut 6 1, 2 and relations with Admiralty 1 differences with Denniston 1 and cultural life at Bletchley Park 1 and reorganisation

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each wheel were used to indicate its precise starting position. The Polish codebreaker Marian Rejewski (TOP LEFT) was the first man to break the ‘steckered’ Enigma machine. The Poles were assisted by information provided by Hans Thilo Schmidt (TOP RIGHT), codenamed Asche, a French spy inside the German Defence Ministry, who sold

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Alexander (LEFT) another of the leading codebreakers and head of the Naval Enigma section Hut 8. RIGHT: A rare photograph of German operators using the Enigma machine. Photographs of the codebreakers working inside the Bletchley Park mansion before the moves to the wooden huts are very rare. Leslie Lambert (TOP), who worked

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settings. Women worked in a wide variety of roles, including codebreaking. These woman are working on the Enigma cyphers in Hut 6. There is an Enigma machine on the table to test solutions. Gordon Welchman, the Cambridge mathematician who set up Hut 6 to break the German Army and Luftwaffe Enigma cyphers

War of Shadows: Codebreakers, Spies, and the Secret Struggle to Drive the Nazis From the Middle East

by Gershom Gorenberg  · 19 Jan 2021  · 555pp  · 163,712 words

a mystery. In the original design, there were close to two billion possible settings.32 In 1926, the navy of the Weimar Republic began using Enigma machines for its communications, followed by the German army in 1928. Nazi Germany’s air force, the Luftwaffe, adopted the machine in 1935.33 Other inventors

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the Zimmermann Telegram. After the Great War, Dilly completed his translation of Herodas but went on working for GC&CS. He acquired an early commercial Enigma machine, though a British expert analyzed the device and decided Britain shouldn’t use Enigma for its own communications. Other countries did adopt the Enigma. Dilly

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, had enough hope to bring in Twinn, Turing, and Welchman.17 When Welchman came to the cottage, someone showed him a copy of a German Enigma machine with the correct wiring and explained the format in which messages were sent. The machine and the explanations, he was told, came from “the Poles

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the Enigma system worked and what was known about the preambles. Once a month, the German code clerks got instructions on how to set their Enigma machines each day. Different parts of the military got different instructions. You could only read a message meant for the air force if you had air

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the repeats in each day’s messages. Where the holes lined up, light would shine through, indicating potential solutions. You could try them on an Enigma machine with that day’s intercepts. In a matter of hours, you’d have the day’s settings. It would work only because the German clerk

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enciphering the wheel setting twice and the clues it provided to discover the daily settings. Rejewski came up with a machine that looked like two Enigma machines tethered together. It could rapidly check settings to see which ones could produce the patterns they found. They called it a bomba, a bomb, perhaps

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plain-language texts, she realized that the twenty-letter sets each day were going through a triple scrambler, similar to the three rotors of an Enigma machine. She rushed into the next room, where the senior staff worked, to ask Rowlett to come see. “Gene has found what we’re looking for

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orders did not come with vehicles. He commandeered a truck and a bus, loaded them with the post’s staffers and files and Polish-made Enigma machines, and headed out into the churning current of refugees on the roads southward.7 Rejewski, Rozycki, and Zygalski were fleeing a German invasion for the

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tested. It’s unlikely that anyone in England would have asked him. The best minds of Bletchley Park assumed that the Poles had pinched an Enigma machine with its wheels, rather than working out the wiring mathematically. After the fall of France, in any case, Rejewski was beyond reach. Dilly Knox’s

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.13 Margaret Storey was working in Hut 6 that winter.14 A standard task for young multilingual women was operating an improvised version of an Enigma machine. The device tested whether a setting suggested by the bombes was, in fact, the one in which a message had been enciphered. If it was

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identified the key used by the German railway administration. It vanished, then reappeared early in 1941. The Nazi railway people used a model of the Enigma machine without a plugboard, which made it easier for John Tiltman to crack the key. By March the number of railway messages multiplied. Most gave instructions

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was dated July 18, 1941, and came from a militarized wing of the police that worked with the SS. The German police did not have Enigma machines. They used a cipher method known as transposition: rearranging the letters of the original text, according to a pattern that shifted daily. At Bletchley Park

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the cottage at Bletchley Park had figured out how to read messages sent between main Abwehr stations with the agency’s special model of the Enigma machine. Knox, dying of cancer, gave credit to Mavis Lever and another woman in his group, Margaret Rock, for solving the puzzle. The value of Abwehr

One Day in August: Ian Fleming, Enigma, and the Deadly Raid on Dieppe

by David O’keefe  · 5 Nov 2020  · 1,243pp  · 167,097 words

(Kriegsmarine) had recently introduced to encrypt its messages before they were sent via wireless. Among these items were ‘specimens of the wheels used on the Enigma machine, particulars of their daily settings for wheels and plugs, codebooks, and all documents relating to signals and communications,’ as well as anything connected with the

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decrypting German navy messages between its headquarters and its surface and U-boat fleets. During that period, German communications were encrypted on a three-wheel Enigma machine – a complex electromechanical rotor cipher machine belonging to a family of devices (the army, navy and air force each had their own version) first developed

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by the Germans at the end of the First World War. To do their work, the cryptanalysts at Bletchley Park relied on pinched material – Enigma machines captured from destroyed submarines, for instance, or, more importantly, the codebooks, rotor-setting sheets and instruction manuals used to unravel the German secret transmissions. So

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of the boat to ensure they had subdued everyone on board, they located and seized their target: a three-rotor version of a German naval Enigma machine with its associated codebooks and setting sheets. Only then did they turn their attention to the captured crew members, whom they quickly ushered to the

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Building in London, had suggested to Fleming that he send a bogus signal to the Germans asking them to resend the upcoming keys for the Enigma machines – keys that changed daily. Politely rejecting the idea, Fleming informed Knox that ‘the possibility should be examined and something got ready and kept ready for

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full advantage of this diversion, Fleming’s commando unit would then board the vessel, capture and kill the German crew, commandeer the vessel and its Enigma machine and cipher aids, and hightail it back to the nearest British port, shadowed by RAF aircraft to prevent prying eyes from spotting the results of

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the war at sea ever-present in their minds, the cryptanalysts had toiled and struggled in vain to produce a breakthrough in decrypting the naval Enigma machine. Fleming reassured Birch that they ‘needed to have no fear that the value of a pinch was underestimated.’11 The magnitude of all these developments

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the century, the world’s navies strove to develop codes and ciphers to protect their top-secret communications from enemy cryptographic efforts. The seemingly impregnable Enigma machine appeared to be the answer for the German navy. Almost every vessel in the fleet was outfitted with this device – from their super-battleships, pocket

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formed the fertile playing ground for John Godfrey and Ian Fleming to pinch the materials so badly needed by the cryptanalysts at Bletchley Park. The Enigma machine came to obsess anyone involved with decryption, no matter how marginal the association. It was an intellectual Everest; enticing, taunting, and at times seeming to

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. The machine could encipher each letter of the alphabet individually, unlike other machines and forms of encryption that encoded complete words, word for word. The Enigma machine was far more subtle and therefore more difficult to crack. It did not actually transmit messages itself, as a wireless or telegraphy set would do

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key or password to unlock the true meaning of the message. With the key sheet in hand, the receiver proceeded in reverse steps, using his Enigma machine to decrypt the message and reveal its meaning in plain German text.17 To pry into an Enigma-enciphered message, cryptanalysts had to establish the

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wade through the data and decipher messages, they believed that any captured materials would yield vastly outdated information. According to a pre-war estimate, one Enigma machine could produce 10.5 quadrillion possible keys for each message, meaning it would take 1,000 enemy cryptanalysts working with four captured or copied keys

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spring, but every success reemphasised the conclusion that as far as wireless was concerned, 95% [of] all worthwhile German naval traffic was enciphered on the Enigma machine. By that time, the pessimism formerly prevailing concerning the chances of ever breaking into naval Enigma had been dispelled, and special machinery, designed for the

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and plain-language traffic of German salvage ships operating in the Channel, and before long they had established a ‘hit list’ of vessels that possessed Enigma machines and related material or other codes that could be used as temporary solutions to the problem. The list focused on four types of vessel: S

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Birch in response to the report, ‘that efforts should be made to capture one of these in circumstances which would prevent the destruction of the Enigma Machine, attachments and papers?’ He could not think how to attempt such a daring exploit himself, so turned it over to NID and the imaginative Ian

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the crew, followed by a tear-gas attack to incapacitate all aboard and prevent ‘destruction of the books and alteration of the settings of the Enigma machines.’ The planners placed great emphasis on this aspect of the mission, directing that the plug settings, locked in position by the commander, be left in

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chances of breaking into the codes by analytical means dropped further. The only way they could make progress was through a steady supply of pinched Enigma machines or parts and the supporting codebooks and setting sheets. Fortunately, because the German navy relied heavily on radio communications to coordinate its actions, equipment of

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out, running her aground and killing her captain in the process. When the boarding party arrived, however, they discovered that the captain had tossed the Enigma machine overboard seconds before his death – but had left other ‘valuable cypher material’ in place, which was seized by the commandos.32 It was this haul

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of seemingly innocent German trawlers their prime objective, as the evidence obtained through traffic analysis and radio fingerprinting indicated that these vessels either used the Enigma machine in their work or maintained other material that Bletchley could use for cribs.35 On that basis, Claymore was ‘planned with this end in view

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analysis, the gifted Harry Hinsley noted that the small vessels, mainly weather-reporting ships, employed a series of codes and ciphers and, at times, the Enigma machine. The odds were therefore extremely high that these lightly armed and thoroughly vulnerable ships could deliver the materials that the experts at Bletchley Park required

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the ship, was in ‘perfect condition,’ with no signs of destruction. Here he found signals books, logbooks and correspondence – and, sitting on the desk, the Enigma machine, still plugged in, as though it had been in use when abandoned. Quickly, Balme organized a human chain and took every book, chart and scrap

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’ that guided ‘the entire memorandum.’78 Part of this foot-dragging stemmed from the reality of bureaucratic limitations. The relatively uncomplicated use of the naval Enigma machine, coupled with its wide distribution, meant that any attempt to replace it would constitute a massive undertaking with enormous financial outlay, delays and the headaches

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one possessed a sinister difference: ‘Schlüssel M4’ and the serial number ‘3172.’94 Immediately, NID and the cryptanalysts understood its watershed implications: an improved naval Enigma machine that employed four rotors and correspondingly four-rotor keys, had made its way aboard Dönitz’s U-boats plying the Atlantic. This dramatic development now

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the best form of cryptography. Nigel de Grey, Room 40 veteran and deputy director of Bletchley Park News that a four-rotor version of the Enigma machine existed did not catch the British by surprise.1 Ten months earlier, in January 1941, John Godfrey had learned from a set of captured instructions

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U-boats, right up to the Tirpitz (the Bismarck’s sister ship) while operating in port, providing cribs and rounding out messages sent via the Enigma machines.14 Used by all vessels of every class in the Kriegsmarine, these messages, seemingly of ‘lesser’ importance, contained information about damage to ships, building progress

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gain invaluable insights into German encryption methods and technology. The only black spot was the failure to uncover anything substantial connected to the four-rotor Enigma machine. With fingers still firmly crossed, the British moved on into a new year and a new war. On December 7, 1941, the Japanese launched their

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It was an extremely challenging time, despite the recent success at Lofoten and Vaagso, because ominous warnings about the imminent introduction of the four-rotor Enigma machine continued to surface. A new series of ‘four-rotor duds’ – setting mistakes by German operators using the new machine as though it were a three

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, as well as with other headquarters in the wireless chain. Regardless of size or location, these headquarters would have to possess various forms of the Enigma machine, along with the associated codebooks, tables and setting sheets, not to mention copies of RHV, short-signal codebooks, weather codes and dockyard ciphers – all of

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usage was a nonsensical waste of valuable resources; the few precious three-wheeled machines were desperately needed to decipher message traffic encrypted on three-rotor Enigma machines from other theatres of war (at this point, the German high command had put the four-rotor machine into operation only in the Atlantic), so

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facilities … [and] had knowledge of new construction, completions and exercises in the Baltic.’18 However, they knew that as the use of the four-rotor Enigma machine spread more widely throughout the German navy, these lower-level codes and ciphers would likely disappear incrementally in the intelligence equation. To meet that possibility

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the last indigenous natural resources that Great Britain possessed. The technology and processes developed in Bletchley Park’s code-breaking huts to exploit both the Enigma machine and, a year later, to build Colossus, the world’s first programmable computer, to break Tunny, were undeclared national treasures that remained wrapped in a

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partners in the war at sea – even if, ideally, they would keep them as limited intelligence partners. That meant that the issues surrounding Germany’s Enigma machine became the major points for discussion in most of their intelligence dealings. Neither side at first rushed into the other’s arms, but despite British

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the United States Navy put a strain on the special relationship. Having waited for more than a year for a reciprocal delivery of the naval Enigma machine they had requested earlier, the US Navy now accused the British of foot-dragging on Enigma-related material. It threatened to withhold further information on

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Park’s too. Armed with the appropriate firepower, the commandos would be able to overtake the local defences, prevent the last-minute destruction of the Enigma machines and their supporting code and cipher books, and get out undetected.30 Second, having a trained commando unit at the ready would give the Admiralty

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and the Naval Section at Bletchley knew that Admiral Karl Dönitz’s U-boats operating in the Atlantic had begun to use the four-rotor Enigma machine to encrypt their top-secret messages. As frightening and potentially cataclysmic as this development certainly was, a more disturbing prospect had appeared just weeks before

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the cryptanalysts was the unintelligible nature of the message, which revealed that it had been mistakenly encrypted using four-rotor settings from the new naval Enigma machine rather than the usual three-rotor settings employed for the home waters key. Immediately, Bletchley and NID realized the ominous nature of the development and

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given shore establishment.’15 As per standard procedure, the Kriegsmarine outfitted each naval shore station (regardless of size or shipping traffic) with at least three Enigma machines, usually located in the local naval headquarters.16 Also, as Dieppe served as a naval supply base for this part of the Channel, it housed

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any information related to Bletchley Park remained above their pay grade.19 They needed only to recognize what was required: the remains of a smashed Enigma machine, samples of its wheels and wooden case, along with specimens of its codebooks, including damaged publications printed with soluble ink.20 In early June, long

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of Naval Intelligence began to pressure the British to uphold their end of the agreement. First, the Americans reiterated a request for a captured naval Enigma machine for research purposes; but handing over a three-rotor machine would not help alleviate the losses off American shores and would reveal to the Americans

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and ‘would welcome our experiences on this subject.’46 In addition to the delicate situation with the Americans, the potential spread of the four-rotor Enigma machine and the deepening crisis at sea were preoccupations in the weeks leading up to Operation Rutter. By early June, in addition to learning earlier that

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Collection Rear Admiral John Godfrey © Imperial War Museums Admiral Karl Dönitz Bundesarchiv (Creative Commons licence CC BY-SA 3.0 DE) The naval four-rotor Enigma machine US National Archives and Records Administration The ‘Morrison Wall’ at Bletchley Park © Crown copyright. By kind permission of Director GCHQ Two sets of spare rotor

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wheels for the Enigma machine © Crown copyright. By kind permission of Director GCHQ Three Enigma rotor wheels laid out on their sides © Crown copyright. By kind permission of Director GCHQ

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, a gifted nineteen year-old cryptanalyst on Knox’s team, her boss ‘would have explained to Fleming what they already knew without capturing the actual Enigma machine – the wireless transmitting routine, manual instruction books, frequencies and message indicators and how it was the document with the daily key settings, and not the

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actual Enigma machine, a model of which they had been given by the Poles, that was required for the breakthrough.’ Mavis Batey, From Bletchley with Love (Bletchley, UK

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Use, p. 153. 15. Jak P. Mallmann Showell, Enigma U-Boats: Breaking the Code (Birmingham, UK: Ian Allan, 2009), 86. Kindle edition. 16. The original Enigma machine, used by the German army and air force, offered only five wheels. 17. B. Jack Copeland, Turing: Pioneer of the Information Age (Oxford: Oxford University

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transmitters, the types of traffic they transmitted and the methods they used to communicate. 7. Two sets of spare rotor wheels for the three-wheel Enigma machine, in their carrying box. 8. Three Enigma rotor wheels laid out on their sides. The alphabet is visible around the edge of the top rotor

Decoding Organization: Bletchley Park, Codebreaking and Organization Studies

by Christopher Grey  · 22 Mar 2012

became in turn a major film of the same title in 2001, whilst another film, U-571 (2000), fictionalized the capture at sea of an Enigma machine. Bletchley Park was satirized in the BBC radio comedy show Hut 33, first broadcast in 2007, and was the subject of a 1999 Channel Four

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; Erskine, 2000; Calvocoressi, 2001: 31–54; Carter, 2010). It is important to understand that, at different times and in different places, different versions of the Enigma machine were used. Enigma presented a challenge of enormous complexity for cryptanalysis since, although varying according to which version of the machine was in use, it

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codebooks from the Germans, partly because of the genius of the BP codebreakers and partly as a result of mistakes made by operators of the Enigma machines, a wartime key was indeed broken, when some messages in the Army Enigma Green key31 were read in January 1940 (Hinsley, 1993c: 14). Gradually, with

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that, for ease of exposition, I have simplified many details, especially those relating to the technical details of cryptanalysis and in particular those relating to Enigma machines. I have also tended to confine very detailed empirical points to endnotes. 3. The abbreviation BP, which was in use there during WW2, will for

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in-house. Thirdly, it was of paramount importance that the source of the intelligence be kept absolutely secret, since were it to be otherwise, the Enigma machine would be modified or abandoned and, hence, the continued breaking of the ciphers would become impossible. Taken together, these things meant that traditional ways of

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activities at various times. One important example may serve to illustrate this. In January 1944 the German Air Force briefly introduced a modification to some Enigma machines, known in German as Umkehrwalze D (UKD) and referred to at BP as Uncle Dick58. This dramatically increased Enigma security and, had it been widely

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). 21. TNA HW 43/70: 24. 22. As noted elsewhere, Typex machines were one of the British cipher machines, themselves based upon pre-war commercial Enigma machines, and like them lacked a plugboard (see the introductory chapter for explanation of the significance of the plugboard). Thus the Typex Room was sending encoded

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e t c h l e y p a r k w o r k 58. The Umkehrwalze was the reflector, or reversing wheel, on Enigma machines, a part of the mechanism for the scrambling of electrical current within the device. The standard reflector was Umkehrwalze B (UKB). The significance of UKD

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key of Naval Enigma, which became unreadable at BP for ten months from 1 February 1942 following the addition of a fourth rotor to the Enigma machines of this user group (Erskine, 2001a: 181). This was militarily crucial because it was the key used by the German U-boats in the North

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genteel interactions, elsewhere in BP such get togethers had a more ebullient feel. The context for this example was a change made to some Army Enigma machines in July 1944, giving rise to a new and initially puzzling version called ‘Enigma Uhr’ (for technical details see Ulbricht, 1999). This was another case

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) transmitted without encipherment, or the text resulting from the decryption of an enciphered message. Plugboard: An electrical (re-cabling) modification of pre-war commercial Enigma machines, made to military Enigma machines, very significantly increasing their security. Hence, ‘plugboard Enigma’ to describe such machines. Room 40: Cryptanalytic section of the Admiralty during WW1 (formally, NID

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enciphered on the Lorenz SZ 40/42 machine, read at BP using Colossus. Typex: British high-grade machine cipher, based upon the pre-war commercial Enigma machine and in that sense simpler than the plugboard version used by German military forces, but never broken. Ultra: A reduction of ‘Top Secret Ultra’. Cover

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from cryptanalysis of high-grade ciphers such as Enigma and Fish. Supplanted the earlier term Boniface from late 1941. Umkehrwalze: Reversing wheel (or reflector) on Enigma machines. The standard version was Umkehrwalze B. A field-rewireable version, Umkehrwalze D (known at BP as Uncle Dick), which massively increased security, was introduced to

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Organization Studies Vol. III. Thousand Oaks, CA: Sage, pp. 1185–8. Streeck, W. 2009. Re-forming Capitalism. Oxford: Oxford University Press. Stripp, A. 1993. ‘The Enigma machine. Its mechanism and use’, in Hinsley, H. and Stripp, A. (eds.), Codebreakers. The Inside Story of Bletchley Park. Oxford: Oxford University Press, pp. 83–8

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between mathematicians and 168 listening stations 188–189 see also Y stations log reading 192, 225, 235 Lucas, F. L. 67 Luftwaffe Enigma see GAF Enigma Machine Co-ordination Development Section 200 Maclean, Donald 207 management style 177, 205 informal 187–190, 231, 238 formal 188–190 gendered pattern 188 and morale

The Code Book: The Science of Secrecy From Ancient Egypt to Quantum Cryptography

by Simon Singh  · 1 Jan 1999

an electrical version of Alberti’s cipher disk. Called Enigma, Scherbius’s invention would become the most fearsome system of encryption in history. Scherbius’s Enigma machine consisted of a number of ingenious components, which he combined into a formidable and intricate cipher machine. However, if we break the machine down into

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the ciphertext, symptoms of a weak cipher. This problem can be alleviated by introducing a second scrambler disk. Figure 33 A simplified version of the Enigma machine with an alphabet of just six letters. The most important element of the machine is the scrambler. By typing in b on the keyboard, a

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, and therefore 17,576 possible starting positions. The initial setting of the scramblers will determine how the message is encrypted. We can think of the Enigma machine in terms of a general cipher system, and the initial settings are what determine the exact details of the encryption. In other words, the initial

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hands it to a radio operator who transmits it to the intended receiver. In order to decipher the message, the receiver needs to have another Enigma machine and a copy of the codebook that contains the initial scrambler settings for that day. He sets up the machine according to the book, types

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, and the codebook that contains it, must never be allowed to fall into enemy hands. It is quite possible that the enemy might capture an Enigma machine, but without knowing the initial settings used for encryption, they cannot easily decrypt an intercepted message. Without the codebook, the enemy cryptanalyst must resort to

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checking all the possible keys, which means trying all the 17,576 possible initial scrambler settings. The desperate cryptanalyst would set up the captured Enigma machine with a particular scrambler arrangement, input a short piece of the ciphertext, and see if the output makes any sense. If not, he would change

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adding more scramblers (each new scrambler increases the number of keys by a factor of 26), but this would have increased the size of the Enigma machine. Instead, he added two other features. First, he simply made the scramblers removable and interchangeable. So, for example, the first scrambler disk could be moved

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ring, which has not yet been mentioned. Although the ring does have some effect on encryption, it is the least significant part of the whole Enigma machine, and I have decided to ignore it for the purposes of this discussion. (Readers who would like to know about the exact role of the

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cipher machine was contained in a compact box measuring only 34 × 28 × 15 cm, but it weighed a hefty 12 kg. Figure 39 shows an Enigma machine with the outer lid open, ready for use. It is possible to see the keyboard where the plaintext letters are typed in, and, above it

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the resulting ciphertext letter. Below the keyboard is the plugboard; there are more than six pairs of letters swapped by the plugboard, because this particular Enigma machine is a slightly later modification of the original model, which is the version that has been described so far. Figure 40 shows an Enigma with

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was brought to trial by dissatisfied shareholders and found guilty under California’s Corporate Securities Act. Figure 39 An army Enigma machine ready for use. (photo credit 3.6) Figure 40 An Enigma machine with the inner lid opened, revealing the three scramblers. Fortunately for Scherbius, however, the German military were eventually shocked into

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appreciating the value of his Enigma machine, thanks to two British documents. The first was Winston Churchill’s The World Crisis, published in 1923, which included a dramatic account of how the

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British command.” The German military held an enquiry into how to avoid repeating the cryptographic fiascos of the First World War, and concluded that the Enigma machine offered the best solution. By 1925 Scherbius began mass-producing Enigmas, which went into military service the following year, and were subsequently used by the

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distinct from the few machines that Scherbius had previously sold to the business community, because the scramblers had different internal wirings. Owners of a commercial Enigma machine did not therefore have a complete knowledge of the government and military versions. Over the next two decades, the German military would buy over 30

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,000 Enigma machines. Scherbius’s invention provided the German military with the most secure system of cryptography in the world, and at the outbreak of the Second World

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War their communications were protected by an unparalleled level of encryption. At times, it seemed that the Enigma machine would play a vital role in ensuring Nazi victory, but instead it was ultimately part of Hitler’s downfall. Scherbius did not live long enough

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40 continued to monitor German communications. In 1926 they began to intercept messages which baffled them completely. Enigma had arrived, and as the number of Enigma machines increased, Room 40’s ability to gather intelligence diminished rapidly. The Americans and the French also tried to tackle the Enigma cipher, but their attempts

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committed patriot who had grown up in the town of Szamotuty, a center of Polish nationalism. Ciezki had access to a commercial version of the Enigma machine, which revealed all the principles of Scherbius’s invention. Unfortunately, the commercial version was distinctly different from the military one in terms of the wirings

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allowed Rex to photograph two documents: “Gebrauchsanweisung für die Chiffriermaschine Enigma” and “Schlüsselanleitung für die Chiffriermaschine Enigma.” These documents were essentially instructions for using the Enigma machine, and although there was no explicit description of the wirings inside each scrambler, they contained the information needed to deduce those wirings. Figure 41 Hans

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. (photo credit 4.1) Thanks to Schmidt’s treachery, it was now possible for the Allies to create an accurate replica of the German military Enigma machine. However, this was not enough to enable them to decipher messages encrypted by Enigma. The strength of the cipher depends not on keeping the machine

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setting of the machine (the key) secret. If a cryptanalyst wants to decipher an intercepted message, then, in addition to having a replica of the Enigma machine, he still has to find which of the millions of billions of possible keys was used to encipher it. A German memorandum put it thus

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Secret Service was clearly up to scratch, having found an informant in Schmidt, and having obtained the documents that suggested the wirings of the military Enigma machine. In comparison, French cryptanalysts were inadequate, and seemed unwilling and unable to exploit this newly acquired information. In the wake of the First World War

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they suffered from overconfidence and lack of motivation. The Bureau du Chiffre did not even bother trying to build a replica of the military Enigma machine, because they were convinced that achieving the next stage, finding the key required to decipher a particular Enigma message, was impossible. As it happened, ten

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. Together, the scrambler arrangement and orientations are known as the scrambler settings. To implement this particular day key, the Enigma operator would set up his Enigma machine as follows: (1) Plugboard settings: Swap the letters A and L by connecting them via a lead on the plugboard, and similarly swap P and

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seemed to be impregnable, but the Polish cryptanalysts were undaunted. They were prepared to explore every avenue in order to find a weakness in the Enigma machine and its use of day and message keys. Foremost in the battle against Enigma was a new breed of cryptanalyst. For centuries, it had been

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it is full of unknowns, but at least it demonstrates that the letters L and R are intimately related by the initial setting of the Enigma machine, the day key. As each new message is intercepted, it is possible to identify other relationships between the 1st and 4th letters of the repeated

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message key. All these relationships are reflections of the initial setting of the Enigma machine. For example, the second message above tells us that M and X are related, the third tells us that J and M are related, and

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times easier, certainly within the realm of human endeavor. Rejewski proceeded as follows. Thanks to Hans-Thilo Schmidt’s espionage, he had access to replica Enigma machines. His team began the laborious chore of checking each of 105,456 scrambler settings, and cataloguing the chain lengths that were generated by each one

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from the plugboard, so that the plugboard had no effect. Finally, he would take a piece of intercepted ciphertext and type it in to the Enigma machine. This would largely result in gibberish, because the plugboard cablings were unknown and missing. However, every so often vaguely recognizable phrases would appear, such as

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devised a mechanized version of his cataloguing system, which could automatically search for the correct scrambler settings. Rejewski’s invention was an adaptation of the Enigma machine, able to rapidly check each of the 17,576 settings until it spotted a match. Because of the six possible scrambler arrangements, it was necessary

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, could fully exploit the concept of the bombe. Table 10 Possible arrangements with five scramblers. Figure 43 General Heinz Guderian’s command post vehicle. An Enigma machine can be seen in use in the bottom left. (photo credit 4.2) On June 30, Major Langer telegraphed his French and British counterparts, inviting

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Enigma replicas and blueprints for the bombes, which were to be shipped in diplomatic bags to Paris. From there, on August 16, one of the Enigma machines was forwarded to London. It was smuggled across the Channel as part of the baggage of the playwright Sacha Guitry and his wife, the actress

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way, it became routine for the cryptanalysts to try out the cillies, and their hunches would sometimes pay off. Cillies were not weaknesses of the Enigma machine, rather they were weaknesses in the way the machine was being used. Human error at more senior levels also compromised the security of the Enigma

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, but once again the implementation of a rule drastically reduced the number of possible keys. This search for new cryptanalytic shortcuts was necessary because the Enigma machine continued to evolve during the course of the war. The cryptanalysts were continually forced to innovate, to redesign and refine the bombes, and to devise

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crib is correct, we can link the letters W→E, e→T, t→W as part of a loop. Although we know none of the Enigma machine settings, we can label the first setting, whatever it is, S. In this first setting we know that w is encrypted as E. After this

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the loop, and saw that they provided him with the drastic shortcut he needed in order to break Enigma. Instead of working with just one Enigma machine to test every setting, Turing began to imagine three separate machines, each dealing with the encipherment of one element of the loop. The first machine

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check all the orientations. Only two problems remained. First, it could be that the three machines are running with the wrong scrambler arrangement, because the Enigma machine operates with any three of the five available scramblers, placed in any order, giving sixty possible arrangements. Hence, if all 17,576 orientations have been

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in parallel. The second problem involved finding the plugboard cablings, once the scrambler arrangement and orientations had been established. This is relatively simple. Using an Enigma machine with the correct scrambler arrangement and orientations, the cryptanalyst types in the ciphertext and looks at the emerging plaintext. If the result is tewwer rather

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was given to the British Tabulating Machinery factory at Letchworth. Figure 49 The loop in the crib can be paralleled by an electrical loop. Three Enigma machines are set up in identical ways, except that the second one has its first scrambler moved forward one place (setting S + 1), and the third

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is right, but he is not sure if he has matched it with the correct letters in the ciphertext. One of the features of the Enigma machine was its inability to encipher a letter as itself, which was a consequence of the reflector. The letter a could never be enciphered as A

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harder to break into than others. The Kriegsmarine network was the hardest of all, because the German Navy operated a more sophisticated version of the Enigma machine. For example, the Naval Enigma operators had a choice of eight scramblers, not just five, which meant that there were almost six times as many

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High Command never suspected that the Allies had pinched Enigma codebooks. If the Germans found that their security had been compromised, they would upgrade their Enigma machines, and Bletchley would be back to square one. As with the Zimmermann telegram episode, the British took various precautions to avoid arousing suspicion, such as

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messages during the war, Britain wanted to continue its intelligence operations, and was reluctant to divulge its capabilities. In fact, Britain had captured thousands of Enigma machines, and distributed them among its former colonies, who believed that the cipher was as secure as it had seemed to the Germans. The British did

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and air force, and the SIGABA (or M-143-C) cipher machine used by the American military. Both these machines were more complex than the Enigma machine and both were used properly, and therefore they remained unbroken throughout the war. Allied cryptographers were confident that complicated electromechanical machine ciphers could guarantee secure

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to encrypt communications between Hitler and his generals. The encryption was performed by the Lorenz SZ40 machine, which operated in a similar way to the Enigma machine, but the Lorenz was far more complicated, and it provided the Bletchley codebreakers with an even greater challenge. However, two of Bletchley’s codebreakers, John

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the encryption techniques described in this book have been symmetric, which means that the unscrambling process is simply the opposite of scrambling. For example, the Enigma machine uses a certain key setting to encipher a message, and the receiver uses an identical machine in the same key setting to decipher it. Similarly

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.attlabs.att.co.uk/andyc/enigma/enigma_j.html http://www.izzy.net/~ian/enigma/applet/index.html Two excellent emulators that show how the Enigma machine works. The former allows you to alter the machine settings, but it is not possible to track the electrical path through the scramblers. The latter

Enigma

by Robert Harris  · 15 Feb 2011  · 387pp  · 111,096 words

Porpoise. And Shark? Shark was the operational cipher of the U-boats. Shark was unique. Every other cipher was produced on a standard three-rotor Enigma machine. But Shark came out of an Enigma with a specially adapted fourth rotor which made it twenty-six times more difficult to break. Only U

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bundle of secret papers from the radio room, handing them to a boarding party in a boat alongside, and had just gone back for the Enigma machine itself when the U-boat suddenly went bows up and sank. They went down with her—half a mile down, the Navy man had said

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been skilful enough, or lucky enough, then in an hour, or a day, the bombe would churn through a million permutations and reveal how the Enigma machine had been set up. That information was relayed back from the bombe bays to the Decoding Room. Because of its noise, the Decoding Room was

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what he was driving at, then, sadly, he would give up on them as a waste of time. On the same principle, Jericho thought the Enigma machine was beautiful—a masterpiece of human ingenuity that created both chaos and a tiny ribbon of meaning. In the early days at Bletchley he used

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million million—and you were looking at a machine that had around 150 million million million different starting positions. It didn't matter how many Enigma machines you captured or how long you played with them. They were useless unless you knew the rotor order, the rotor starting positions and the plugboard

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. The larger of the two keys unlocked the door to the museum. Stacked on metal shelves along one wall were a dozen or more captured Enigma machines. The smaller key fitted one of a pair of big iron safes. Jericho knelt and opened it and began to rummage through the contents. Here

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Germans have got a whisper of what we're up to here. What would they do? They couldn't exactly chuck out a hundred thousand Enigma machines overnight, could they? And then what about all those experts of theirs, who've always said Enigma is unbreakable? They're not going to change

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place with a loud metallic click. Each was wired to mimic the action of a single Enigma rotor: 108 in all, equivalent to thirty-six Enigma machines running in parallel. When all the drums had been set, the bombe was trundled back into place and the motor started. The drums began to

The Woman Who Smashed Codes: A True Story of Love, Spies, and the Unlikely Heroine Who Outwitted America's Enemies

by Jason Fagone  · 25 Sep 2017  · 592pp  · 152,445 words

turned with the application of electrical current. Called rotors, these electrified wheels represented an important advance that would find more sophisticated expression in the German Enigma machine; rotors could be easily removed, swapped, and linked in a chain. William asked Hebern how he happened to think of this elegant concept of a

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. President Roosevelt used SIGABAs to communicate from his Hyde Park home and when he traveled on the presidential train. The SIGABA was like an American Enigma machine or Purple machine, only inviolate. No enemy codebreaker, whether German, Italian, or Japanese, would ever manage to break it, despite strenous efforts; the Nazis ultimately

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examine one of the cipher machines she kept there in case she should encounter a message that had been generated by one. She had an Enigma machine on the shelf, an old version that had been freely available in the 1920s. She also had a Kryha there, the semicircular German device that

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have been writing equations, but she was thinking mathematically. This is also why, in 1940, when Elizebeth encountered her first Enigma messages from a German Enigma machine, she didn’t feel overly intimidated. Enigma was a straightforward idea expressed in a diabolical device. In the simplest sense, it was a box that

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its own ULTRA factories in Washington and sharing the burden. But early in the war, when Elizebeth and her coast guard unit analyzed their first Enigma machine, ULTRA was a strictly British franchise. There was no one to tell the Americans what to do. They had to invent their own method. At

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, a B never meant B. This suggested an Enigma. They went to the shelf in their coast guard office and picked up their old commercial Enigma machine. The codebreakers had already solved most of the messages, but now they wondered if they could solve the machine itself—the wiring. Knowing the wiring

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coffee, and identifying cribs to feed into the bombes, while others operated the bombes that ticked and whirred as they explored the keyspaces of distant Enigma machines. The buildings were hot and unventilated. An Arlington Hall codebreaker named Martha Waller recalled that in the summer, it was often 90 degrees indoors at

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messages on October 10, 1942. The messages seemed to resist solution. She wondered if it might be an Enigma circuit, the messages encrypted by an Enigma machine of some kind. She called it Circuit 3-N. Presumably the messages on Circuit 3-N were sensitive enough to require a stronger-than-usual

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arrived in Elizebeth’s office each week. By December 1942 she had accumulated twenty-eight encrypted messages. A cursory analysis showed telltale signatures of an Enigma machine. Elizebeth and the coast guard had already solved one Enigma, back in 1940, a commercial Enigma whose wiring scheme was already known. Now they were

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will be ours.” At her coast guard desk, Elizebeth reached for a fresh sheet of grid paper. Circuit 3-N. Argentina to Berlin. The unknown Enigma machine. Twenty-eight unsolved messages from Circuit 3-N now sat in a pile on her desk. She wrote the twenty-eight ciphertexts on the worksheet

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of another, assembling a stack of text so she could solve the messages in depth, like she had done in 1940 to solve the commercial Enigma machine. The twenty-eight messages all appeared to use the same key—a huge gift to the codebreakers from their Nazi adversaries. It made things easier

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and her team—had broken his cipher machines and were now reading his every transmission, but for Utzinger, the prospect of a Yankee breaking an Enigma machine was beyond his comprehension. This wasn’t to say that he slept soundly at night; like any good radio expert, Utzinger lived in a fog

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, and Utzinger asked Berlin to smuggle them a new cipher device through Becker’s network of wolves. Instead of a Kryha, Berlin sent a new Enigma machine. “Enigma arrived via RED,” Utzinger reported to Berlin on November 4, 1943. “Thank you very much.” He typed this message on his older

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Enigma machine, the Green machine. He went on, “From our message 150 we shall encipher with the new Enigma . . . LUNA.” “It is a birthday surprise for LUNA,”

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when you woke up groggy and confused, and your kidney was sitting in a bowl of ice on the counter. She knew about the new Enigma machine sent to Argentina in November 1943—the Red Enigma—because the spies had discussed its delivery in Green messages and she had been reading those

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of Siegfried Becker. Becker: a character out of a novel. A Nazi spy with long curling fingernails. A man who carried explosives in trunks and Enigma machines in his luggage. A seducer of the wives of Brazilian politicians. A stowaway on ocean-crossing ships. An SS-Hauptsturmführer who wore the ring of

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the FBI didn’t intercept the messages. It didn’t monitor the Nazi circuits. It didn’t break the codes. It didn’t solve any Enigma machines. The coast guard did this stuff—the little codebreaking team that Elizebeth created from nothing. During the Second World War, an American woman figured out

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clandestine Nazi messages that her team shared with the global intelligence community. She had conquered at least forty-eight different clandestine radio circuits and three Enigma machines to get these plaintexts. The pages found their way to the navy and to the army. To FBI headquarters in Washington and bureaus around the

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and suggest questions. After listening to the POWs and analyzing the documents, William concluded that Germany had never lost faith in the security of the Enigma machine. They thought Enigma was unbreakable all the way to the end. He was proud to learn that Nazi codebreakers had never managed to defeat America

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), xviii. one to five messages per day “History of USCG Unit #387,” 216–30. All details from the coast guard’s solution to this first Enigma machine are documented here. 200 a linguist and scholar Mavis Batey, “Knox, (Alfred) Dillwyn (1884–1943),” 2004, rev. ed. 2006, Oxford Dictionary of National Biography, http

The Information: A History, a Theory, a Flood

by James Gleick  · 1 Mar 2011  · 855pp  · 178,507 words

’s end, the Turing Bombes were deciphering thousands of military intercepts every day: processing information, that is, on a scale never before seen. A CAPTURED ENIGMA MACHINE (Illustration credit 7.1) Although nothing of this passed between Turing and Shannon when they met for meals at Bell Labs, they did talk indirectly

The Codebreakers: The Comprehensive History of Secret Communication From Ancient Times to the Internet

by David Kahn  · 1 Feb 1963  · 1,799pp  · 532,462 words

, but when in 1928 messages with quite different letter frequencies appeared, it failed. Through analysis or spies, it learned that the new system was the Enigma machine. And here the head of the Biuro Szyfrów proved himself more farsighted than any country’s cryptanalytic chief in the 1920s. Franciszek Pokorny recognized that

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the struggle. And by doing so, it saved lives. And what contribution could be greater than that? The great story of the solution of the Enigma machine and its effects on World War II remained a tightly held secret for almost 30 years. Only a few tiny shards of light about it

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for decades—probably the best example of general security in history. The British government insisted upon this silence because it had given the thousands of Enigma machines that it had gathered up after the end of the war to its former colonies as they gained independence and needed secure systems of communication

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using shift registers, cryptosystems based on elliptic curves and other mathematical techniques—all are implemented today not on the alphabet of 26 letters, as the Enigma machine and the hand cipher systems of yesteryear were, but on the binary digital alphabet of 0s and 1s. The reason is that this is the

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