In cryptography, a cipher is an algorithm for performing encryption or decryption—a series of well-defined steps that can be followed as a procedure. An alternative, less common term is encipherment, to encipher or encode is to convert information into cipher or code. In common parlance, cipher is synonymous with code, as they are both a set of steps that encrypt a message, the concepts are distinct in cryptography, especially classical cryptography. Codes generally substitute different length strings of characters in the output, there are exceptions and some cipher systems may use slightly more, or fewer, characters when output versus the number that were input. Codes operated by substituting according to a large codebook which linked a random string of characters or numbers to a word or phrase, for example, UQJHSE could be the code for Proceed to the following coordinates. When using a cipher the original information is known as plaintext, the ciphertext message contains all the information of the plaintext message, but is not in a format readable by a human or computer without the proper mechanism to decrypt it.
The operation of a cipher usually depends on a piece of auxiliary information, the encrypting procedure is varied depending on the key, which changes the detailed operation of the algorithm. A key must be selected using a cipher to encrypt a message. Without knowledge of the key, it should be difficult, if not impossible. Most modern ciphers can be categorized in several ways By whether they work on blocks of symbols usually of a fixed size, by whether the same key is used for both encryption and decryption, or if a different key is used for each. If the algorithm is symmetric, the key must be known to the recipient and sender, if the algorithm is an asymmetric one, the enciphering key is different from, but closely related to, the deciphering key. If one key cannot be deduced from the other, the asymmetric key algorithm has the key property. The word cipher in former times meant zero and had the same origin, Middle French as cifre and Medieval Latin as cifra, cipher was used for any decimal digit, even any number.
There are many theories about how the word cipher may have come to mean encoding, the Roman number system was very cumbersome because there was no concept of zero. Cipher came to mean concealment of clear messages or encryption, the French formed the word chiffre and adopted the Italian word zero. The English used zero for 0, and cipher from the word ciphering as a means of computing, the Germans used the words Ziffer and Chiffre. The Dutch still use the word cijfer to refer to a numerical digit, the Serbians use the word cifra, which refers to a digit, or in some cases, any number. Besides cifra, they use word broj for a number, the Italians and the Spanish use the word cifra to refer to a number
The Enigma machines were a series of electro-mechanical rotor cipher machines developed and used in the early- to mid-twentieth century to protect commercial and military communication. Enigma was invented by the German engineer Arthur Scherbius at the end of World War I, early models were used commercially from the early 1920s, and adopted by military and government services of several countries, most notably Nazi Germany before and during World War II. Several different Enigma models were produced, but the German military models, however and Italian models were in use. Rejewski did that without knowing the machine wiring, so the result did not allow the Poles to read any messages, the French had a spy with access to German cipher materials that included the daily keys used in September and October 1932. Those keys included the plugboard settings, the French gave the material to the Poles, and Rejewski used some of that material and the message traffic in September and October to solve for the unknown rotor wiring.
Consequently, the Poles were able to build their own Enigma machines, Rejewski was aided by cryptanalysts Jerzy Różycki and Henryk Zygalski, both of whom had been recruited with Rejewski from Poznań University. The Polish Cipher Bureau developed techniques to defeat the plugboard and find all components of the daily key, over time, the German cryptographic procedures improved, and the Cipher Bureau developed techniques and designed mechanical devices to continue breaking the Enigma traffic. In 1938, the Germans added complexity to the Enigma machines that finally became too expensive for the Poles to counter. The Poles had six bomby, but when the Germans added two more rotors, ten times as many bomby were needed, but the Poles did not have the resources, the demonstration represented a vital basis for the British continuation and effort. During the war, British cryptologists decrypted a vast number of messages enciphered on Enigma, the intelligence gleaned from this source, codenamed Ultra by the British, was a substantial aid to the Allied war effort.
Like other rotor machines, the Enigma machine is a combination of mechanical and electrical subsystems, the mechanical parts act in such a way as to form a varying electrical circuit. When a key is pressed, one or more move to form a new rotor configuration. Current flows through various components in the new configuration, ultimately lighting one display lamp, which shows the output letter. For example, when encrypting a message starting ANX. the operator would first press the A key, the operator would next press N, and X in the same fashion, and so on. Current flowed from the battery through a depressed bi-directional keyboard switch to the plugboard, next, it passed through the plug A via the entry wheel, through the wiring of the three or four installed rotors, and entered the reflector. The repeated changes of electrical path through an Enigma scrambler implemented a polyalphabetic substitution cipher that provided Enigmas security, the diagram on the right shows how the electrical pathway changed with each key depression, which caused rotation of at least the right-hand rotor.
Current passed into the set of rotors and back out of the reflector, the greyed-out lines are other possible paths within each rotor, these are hard-wired from one side of each rotor to the other. The letter A encrypts differently with consecutive key presses, first to G and this is because the right-hand rotor has stepped, sending the signal on a completely different route
Ultra eventually became the standard designation among the western Allies for all such intelligence. Several other cryptonyms had been used for such intelligence, British intelligence first designated it Boniface—presumably to imply that it was the result of human intelligence. The U. S. used the codename Magic for its decrypts from Japanese sources, much of the German cipher traffic was encrypted on the Enigma machine. Used properly, the German military Enigma would have been virtually unbreakable, in practice, the term Ultra has often been used almost synonymously with Enigma decrypts. However, Ultra encompassed decrypts of the German Lorenz SZ 40/42 machines that were used by the German High Command, many observers, at the time and later, regarded Ultra as immensely valuable to the Allies. F. W. Winterbotham quoted the western Supreme Allied Commander, Dwight D. Eisenhower, the existence of Ultra was kept secret for many years after the war. After it was revealed in the middle 1970s, historians have altered the historiography of World War II, when he put Rommels picture up in his caravan he wanted to be seen to be almost reading his opponents mind.
In fact he was reading his mail, over time Ultra has become embedded in the public consciousness and Bletchley Park has become a significant visitor attraction. In the early phases of the war, particularly during the eight-month Phoney War and this meant that those at Bletchley Park had some time to build up experience of collecting and starting to decrypt messages on the various radio networks. German Enigma messages were the source, with those of the Luftwaffe predominating, as they used radio more. Enigma refers to a family of electro-mechanical rotor cipher machines and these produced a polyalphabetic substitution cipher and were widely thought to be unbreakable in the 1920s, when a variant of the commercial Model D was first used by the Reichswehr. The German Army, Air Force, Nazi party, the commercial versions were not as secure and Dilly Knox of GC&CS, is said to have broken one before the war. The Poles read Enigma to the outbreak of World War II and beyond, at the turn of 1939, the Germans made the systems ten times more complex, which required a tenfold increase in Polish decryption equipment, which they could not meet.
On 25 July 1939, the Polish Cipher Bureau handed reconstructed Enigma machines and their techniques for decrypting ciphers to the French, the Poles early start at breaking Enigma and the continuity of their success, gave the Allies an advantage when World War II began. In June 1941, the Germans started to introduce on-line stream cipher teleprinter systems for strategic point-to-point radio links, several systems were used, principally the Lorenz SZ 40/42 and Geheimfernschreiber. These cipher systems were cryptanalysed, particularly Tunny, which the British thoroughly penetrated and it was eventually attacked using Colossus, which were the first digital programme-controlled electronic computers. The eventual bulk decryption of Lorenz-enciphered messages contributed significantly and perhaps decisively, the Tunny story has become much less well-known among the public than the Enigma one. At Bletchley Park, some of the key responsible for success in the Tunny effort included mathematicians W. T
Signal Intelligence Service
The Signal Intelligence Service was the United States Army codebreaking division, headquartered at Arlington Hall. It was a part of the Signal Corps so secret that outside the office of the Chief Signal officer, SIS was an early predecessor to the NSA and appropriated by the National Security Council who reappointed the resources into the modern National Security Agency. William Friedman began the division with three junior cryptanalysts in April 1930 and their names were Frank Rowlett, Abraham Sinkov, and Solomon Kullback. Before this, all three of them had been mathematics teachers with no cryptanalysis background, Friedman was a geneticist who developed his expertise in cryptology at George Fabyans Riverbank Laboratories Cipher Department during 1915 to 1917. Besides breaking foreign codes, they were responsible for just about anything to do with the War Departments code systems, the SIS initially worked on an extremely limited budget, lacking the equipment it needed to even intercept messages to practice decrypting.
In 1943, the Army Signal Intelligence Service began intercepting Soviet intelligence traffic sent mainly from New York City—assigning the code name Venona to the project, by 1945, some 200,000 messages had been transcribed, a measure of Soviet activity. On 20 December 1946, Meredith Gardner made the first break into the Venona code, after intense study of the Japanese language, I was stationed at Arlington Hall as part of the 2nd Sig Serv Bn. I was given training in cryptography at Vint Hills Farms before the stint at Arlington Hall and we were reading the 1944 Japanese Army General Codebook. There were always glitches, both from faulty reception and failure to break the monthly cyphers and it was our job to fill these in and get the translated messages to McArthurs HQ in the Pacific. We were aided by several two-story barracks filled with IBM computers, in January, the new 1945 codebook was published by the Japanese and we were pretty much back to square one. Myself and another expendable Lt.
were sent to the Pacific looking for captured code equipment and our knowledge of what it looked like would supposedly qualify us to find such. 1st Marines did find the books in the catacombs under Shuri Castle. Back at AH we translated and decrypted, until one day I got a message with a new word, from there it was to Japan to interview civilians and military. Then discharge and back to Texas
Elizebeth Smith Friedman
Elizebeth Smith Friedman was a cryptanalyst and author, and a pioneer in U. S. cryptography. She has been dubbed Americas first female cryptanalyst and she was the wife of William F. Friedman, a notable cryptographer credited with numerous contributions to cryptology, whom she introduced to the field. She enjoyed successes in her own right. Born in Huntington, Indiana to John M. Smith, a Quaker dairyman and politician, the unusual spelling of her name is attributed to her mother, who disliked the prospect of Elizebeth ever being called Eliza. After briefly attending The College of Wooster in Ohio, she graduated from Hillsdale College in Michigan with a major in English literature and was a member of Pi Beta Phi. Having exhibited her interest in languages, she had studied Latin and German, only she and one other sibling were privileged to attend college. Elizebeth Friedman was interviewed by a librarian at Riverbank Laboratories, who spoke with Colonel George Fabyan. The librarian conveyed Smiths love for Shakespeare, among other things, Fabyan, a wealthy textile merchant, soon met Friedman, and they discussed what life would be like at Riverbank, Fabyans great estate located in Geneva, Illinois.
At Riverbank Laboratories Friedman found one of the first such facilities in the US to seriously study cryptography, through the work of the Friedmans, much historical information on secret writing was gathered. Until the World War I creation of MI8, the Armys Cipher Bureau, military cryptography had been officially deemphasized after the Civil War. During World War I, several US Government departments asked Riverbank Labs for help or sent personnel for training, among those was Agnes Meyer Driscoll who came on behalf of the Navy. Among the staff of fifteen at Riverbank was the man Elizebeth would marry in May 1917, the couple worked together for the next four years or so in the only significant cryptographic facility in the country, save Herbert Yardleys Black Chamber. In 1921 Mr. and Mrs. Friedman left Riverbank to work for the War Department in Washington, D. C. Mrs. Friedmans employment as a cryptanalyst for the U. S. Navy followed in 1923 and her career at both is quite significant and embraces cryptography against international smuggling and drug running in various parts of the world.
The smugglers and runners resorted to encrypted radio messages to support their operations and this became a mistaken notion after Mrs. Friedman came to Washington. The Volstead Act of 1919 forbade the manufacture, import, prevailing conditions during those days, encouraged illegal activity. Further, as equipment became less cumbersome, less conspicuous. To avoid taxes, etc. criminals smuggled liquor and, to a degree, perfume, jewels
Finnish Defence Intelligence Agency
The Finnish Intelligence Research Establishment was a signals intelligence unit of the Finnish Defence Forces, founded in 1960 and disestablished in 2014. It was a part of the organization of the Finnish Air Force and it was a part of the Finnish Military Intelligence Service. Very little information about the unit was publicly available, in 1998 it had a budget of 51 million Finnish Markka and a staff of 189. In 2004 the budget was 12.2 million euro and personnel 125, operation Stella Polaris Catalina affair Yrjö Viitasaari, Lord of the Classified Information - Helsingin Sanomat June 5,2001 Douglas C-47 at spyflight. co. uk
Bletchley Park was the central site for British codebreakers during World War II. Run by the Government Code and Cypher School, it penetrated the secret communications of the Axis Powers – most importantly the German Enigma. Located in Milton Keynes, England UK, Bletchley Park is open to the public, Bletchley Park is opposite Bletchley railway station. It is close to junctions 13 and 14 of the M1, located 50 miles northwest of London, the site appears in the Domesday Book as part of the Manor of Eaton. Browne Willis built a mansion there in 1711, but after Thomas Harrison purchased the property in 1793 this was pulled down and it was first known as Bletchley Park after its purchase by Samuel Lipscomb Seckham in 1877. A key advantage seen by Sinclair and his colleagues was Bletchleys geographical centrality, Bletchley Park was known as B. P. to those who worked there. Station X, London Signals Intelligence Centre, and Government Communications Headquarters were all cover names used during the war, the formal posting of the many Wrens – members of the Womens Royal Naval Service – working there, was to HMS Pembroke V.
Royal Air Force names of Bletchley Park and its outstations included RAF Eastcote, RAF Lime Grove, the postal address that staff had to use was Room 47, Foreign Office. Commander Alastair Denniston was operational head of GC&CS from 1919 to 1942, beginning with its formation from the Admiraltys Room 40, key GC&CS cryptanalysts who moved from London to Bletchley Park included John Tiltman, Dillwyn Dilly Knox, Josh Cooper, and Nigel de Grey. These people had a variety of backgrounds – linguists, chess champions, and crossword experts were common, the British War Office recruited top solvers of cryptic crossword puzzles, as these individuals had strong lateral thinking skills. On the day Britain declared war on Germany, Denniston wrote to the Foreign Office about recruiting men of the professor type, personal networking drove early recruitments, particularly of men from the universities of Cambridge and Oxford. Trustworthy women were recruited for administrative and clerical jobs. Later-recruited cryptanalysts included the mathematicians Derek Taunt, Jack Good, Bill Tutte, and Max Newman, historian Harry Hinsley, joan Clarke was one of the few women employed at Bletchley as a full-fledged cryptanalyst.
This eclectic staff of Boffins and Debs caused GC&CS to be dubbed the Golf and Chess Society. During a September 1941 morale-boosting visit, Winston Churchill reportedly remarked to Denniston, I told you to leave no stone unturned to get staff, but I had no idea you had taken me so literally. Six weeks later, having failed to get sufficient typing and unskilled staff to achieve the productivity that was possible, Welchman and Milner-Barry wrote directly to Churchill. His response was Action this day make sure they have all they want on extreme priority and report to me that this has been done. At the end of the week, a worker went off at 8 a. m
Siemens and Halske T52
The instrument and its traffic were codenamed Sturgeon by British cryptanalysts. It fulfilled a role to the Lorenz cipher machines in the German Army. The teleprinters of the day emitted each character as five parallel bits on five lines, typically encoded in the Baudot code or something similar. The T52 had ten pinwheels, which were stepped in a nonlinear way, based in models on their positions from various delays in the past. The numbers of pins on all the wheels were coprime, and this produced a much more complex cipher than the Lorenz machine, and means that the T52 is not just a pseudorandom number generator-and-XOR cipher. Siemens produced several and mostly incompatible versions of the T52, the T52a and T52b, which differed only in their electrical noise suppression, in addition, a number of conceptual flaws, including very subtle ones, had been eliminated. One such flaw was the ability to reset the keystream to a fixed point, following the occupation of Denmark and Norway, the Germans started to use a teleprinter circuit which ran through Sweden.
The Swedes immediately tapped the line, in May 1940, the telephone company Ericsson manufactured a number of T52 analogue machines that could decode the messages once the key settings had been found by hand. The Swedes read traffic in the system for three years, not only between Berlin and Oslo, but between Germany and the German forces in Finland, and of course the German embassy in Stockholm. In total, the Swedes intercepted 500,000 German messages, poor security meant the Germans eventually became aware of this. An improvement in T52 security in 1942 was defeated by the Swedes, however, a second upgrade in mid-1943 was not, and the flow of decrypted messages came to an end. The British first detected T52 traffic in the summer and autumn of 1942 on a link between Sicily and Libya, codenamed Sturgeon, and another from the Aegean to Sicily, codenamed Mackerel. Operators of both links were in the habit of enciphering several messages with the machine settings, producing large numbers of depths.
These depths were analysed by Michael Crum, the British at Bletchley Park also broke into Sturgeon, although they did not break it as regularly as they broke Enigma or Tunny. SIGABA Typex Siemens AG Donald W. Davies, The Siemens and Halske T52e Cipher Machine Donald W. Davies, The Early Models of the Siemens and Halske T52 Cipher Machine Donald W
Marian Adam Rejewski was a Polish mathematician and cryptologist who reconstructed the Nazi German military Enigma cipher machine sight-unseen in 1932. The intelligence that was gained by the British from Enigma decrypts formed part of what was code-named Ultra, in 1929, while studying mathematics at Poznań University, Rejewski attended a secret cryptology course conducted by the Polish General Staffs Cipher Bureau, which he joined in September 1932. The Bureau had had no success in reading Enigma-enciphered messages and set Rejewski to work on the problem in late 1932, Rejewski and his two colleagues developed successive techniques for the regular decryption of Enigma messages. His contributions included the card catalog, derived using the cyclometer that he had invented. Five weeks before the German invasion of Poland in 1939, Rejewski and colleagues presented their achievements to French, shortly after the outbreak of war, the Polish cryptologists were evacuated to France, where they continued breaking Enigma-enciphered messages.
They and their staff were again compelled to evacuate after the fall of France in June 1940. After the French Free Zone was occupied by Germany in November 1942, Rejewski and Zygalski fled via Spain, there they enlisted in the Polish Armed Forces and were put to work solving low-grade German ciphers. After the war, Rejewski reunited with his family in Poland and he died at age 74 of a heart attack and was interred with military honors at Warsaws Powązki Military Cemetery. Marian Rejewski was born 16 August 1905 in Bromberg in the Prussian Province of Posen to Józef and Matylda, after completing secondary school, he studied mathematics at Poznań Universitys Mathematics Institute, housed in Poznań Castle. Rejewski and fellow students Henryk Zygalski and Jerzy Różycki were among the few who could keep up with the course while balancing the demands of their normal studies, on 1 March 1929 Rejewski graduated with a Master of Philosophy degree in mathematics. A few weeks after graduating, and without having completed the Cipher Bureaus cryptology course, he began the first year of a two-year actuarial statistics course at Göttingen, Germany.
He did not complete the course, because while home for the summer of 1930, he accepted an offer, from Professor Krygowski. He began working part-time for the Cipher Bureau, which by had set up an outpost at Poznań to decrypt intercepted German radio messages, Rejewski worked some twelve hours a week near the Mathematics Institute in an underground vault referred to puckishly as the Black Chamber. The Poznań branch of the Cipher Bureau was disbanded in the summer of 1932, in Warsaw, on 1 September 1932, Zygalski, and Różycki joined the Cipher Bureau as civilian employees working at the General Staff building. Their first assignment was to solve a four-letter code used by the Kriegsmarine, progress was initially slow, but sped up after a test exchange—consisting of a six-group signal, followed by a four-group response—was intercepted. The cryptologists guessed correctly that the first signal was the question, on 20 June 1934 Rejewski married Irena Maria Lewandowska, daughter of a prosperous dentist.
The couple eventually had two children, a son, born in 1936, and a daughter, Janina would become a mathematician like her father. The Enigma machine was a device, equipped with a 26-letter keyboard and 26 lamps
Military intelligence is a military discipline that uses information collection and analysis approaches to provide guidance and direction to commanders in support of their decisions. In order to provide an analysis, the information requirements are first identified. These information requirements are incorporated into intelligence collection, analysis. Areas of study may include the environment, hostile and neutral forces, the civilian population in an area of combat operations. Intelligence activities are conducted at all levels, from tactical to strategic, in peacetime, the period of transition to war, most governments maintain a military intelligence capability to provide analytical and information collection personnel in both specialist units and from other arms and services. The military intelligence capabilities interact with civilian intelligence capabilities to inform the spectrum of political, personnel selected for intelligence duties may be selected for their analytical abilities and personal intelligence before receiving formal training.
Intelligence operations are carried out throughout the hierarchy of political and military activity, strategic intelligence is concerned with broad issues such as economics, political assessments, military capabilities and intentions of foreign nations. Operational intelligence is focused on support or denial of intelligence at operational tiers, operational tier is below strategic level of leadership and refers to the design of practical manifestation. Tactical intelligence is focused on support to operations at the tactical level, at the tactical level, briefings are delivered to patrols on current threats and collection priorities. These patrols are debriefed to elicit information for analysis and communication through the reporting chain, Intelligence should respond to the needs of the commander, based on the military objective and the outline plans for the operation. The military objective provides a focus for the process, from which a number of information requirements are derived. In response to the requirements, the analysis staff trawls existing information.
Where gaps in knowledge exist, the staff may be able to task collection assets to collect against the requirement, analysis reports draw on all available sources of information, whether drawn from existing material or collected in response to the requirement. The analysis reports are used to inform the planning staff. This process is described as Collection Co-ordination and Intelligence Requirement Management, the process of intelligence has four phases, analysis and dissemination. In the United Kingdom these are known as direction, processing, many of the most important facts are well known or may be gathered from public sources. This form of collection is known as open source intelligence. For example, the population, ethnic make-up and main industries of a region are important to military commanders