|
Tommy Flowers
Thomas Harold Flowers MBE (22 December 1905 – 28 October 1998) was an English engineer with the British General Post Office. During World War II, Flowers designed and built Colossus, the world's first programmable electronic computer, to help decipher encrypted German messages. Early life Flowers was born at 160 Abbott Road, Poplar in London's East End on 22 December 1905, the son of a bricklayer. Whilst undertaking an apprenticeship in mechanical engineering at the Royal Arsenal, Woolwich, he took evening classes at the University of London to earn a degree in electrical engineering. In 1926, he joined the telecommunications branch of the General Post Office (GPO), moving to work at the Post Office Research Station at Dollis Hill in north-west London in 1930. In 1935, he married Eileen Margaret Green and the couple later had two children, John and Kenneth. From 1935 onward, he explored the use of electronics for telephone exchanges and by 1939, he was convinced that an all ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bletchley Park
Bletchley Park is an English country house and estate in Bletchley, Milton Keynes ( Buckinghamshire) that became the principal centre of Allied code-breaking during the Second World War. The mansion was constructed during the years following 1883 for the financier and politician Sir Herbert Leon in the Victorian Gothic, Tudor, and Dutch Baroque styles, on the site of older buildings of the same name. During World War II, the estate housed the Government Code and Cypher School (GC&CS), which regularly penetrated the secret communications of the Axis Powersmost importantly the German Enigma and Lorenz ciphers. The GC&CS team of codebreakers included Alan Turing, Gordon Welchman, Hugh Alexander, Bill Tutte, and Stuart Milner-Barry. The nature of the work at Bletchley remained secret until many years after the war. According to the official historian of British Intelligence, the " Ultra" intelligence produced at Bletchley shortened the war by two to four years, and without ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buckinghamshire
Buckinghamshire (), abbreviated Bucks, is a ceremonial county in South East England that borders Greater London to the south-east, Berkshire to the south, Oxfordshire to the west, Northamptonshire to the north, Bedfordshire to the north-east and Hertfordshire to the east. Buckinghamshire is one of the Home Counties, the counties of England that surround Greater London. Towns such as High Wycombe, Amersham, Chesham and the Chalfonts in the east and southeast of the county are parts of the London commuter belt, forming some of the most densely populated parts of the county, with some even being served by the London Underground. Development in this region is restricted by the Metropolitan Green Belt. The county's largest settlement and only city is Milton Keynes in the northeast, which with the surrounding area is administered by Milton Keynes City Council as a unitary authority separately to the rest of Buckinghamshire. The remainder of the county is administered by Bu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
D-Day
The Normandy landings were the landing operations and associated airborne operations on Tuesday, 6 June 1944 of the Allied invasion of Normandy in Operation Overlord during World War II. Codenamed Operation Neptune and often referred to as D-Day, it was the largest seaborne invasion in history. The operation began the liberation of France (and later western Europe) and laid the foundations of the Allied victory on the Western Front. Planning for the operation began in 1943. In the months leading up to the invasion, the Allies conducted a substantial military deception, codenamed Operation Bodyguard, to mislead the Germans as to the date and location of the main Allied landings. The weather on D-Day was far from ideal, and the operation had to be delayed 24 hours; a further postponement would have meant a delay of at least two weeks, as the invasion planners had requirements for the phase of the moon, the tides, and the time of day that meant only a few days each month wer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Known-plaintext Attack
The known-plaintext attack (KPA) is an attack model for cryptanalysis where the attacker has access to both the plaintext (called a crib), and its encrypted version (ciphertext). These can be used to reveal further secret information such as secret keys and code books. The term "crib" originated at Bletchley Park, the British World War II decryption operation, where it was defined as: History The usage "crib" was adapted from a slang term referring to cheating (e.g., "I cribbed my answer from your test paper"). A "crib" originally was a literal or interlinear translation of a foreign-language text—usually a Latin or Greek language, Greek text—that students might be assigned to translate from the original language. The idea behind a crib is that cryptologists were looking at incomprehensible ciphertext In cryptography, ciphertext or cyphertext is the result of encryption performed on plaintext using an algorithm, called a cipher. Ciphertext is also known as encrypted o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Tabulating Machine Company
__NOTOC__ The British Tabulating Machine Company (BTM) was a firm which manufactured and sold Hollerith unit record equipment and other data-processing equipment. During World War II, BTM constructed some 200 "bombes", machines used at Bletchley Park to break the German Enigma machine ciphers. The company was formed in 1902 as The Tabulator Limited, after Robert Porter obtained the rights to sell Herman Hollerith's patented machines from the US Tabulating Machine Company (later to become IBM). By 1909, the company had been renamed the "British Tabulating Machine Company Limited". In 1920, the company moved from London to Letchworth, Hertfordshire; it was also at this point that it started manufacturing its own machines, rather than simply reselling Hollerith equipment. Annual revenues were £6K in 1915, £122K in 1925, and £170K in 1937. In 1916 there were 45 staff; this increased to 132 in 1922, 326 in 1929 and 1,225 in 1939. In return for the exclusive right to market Holl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gordon Welchman
William Gordon Welchman (15 June 1906 – 8 October 1985) was a British mathematician. During World War II, he worked at Britain's secret codebreaking centre, "Station X" at Bletchley Park, where he was one of the most important contributors. After the war he moved to the US, and worked on the design of military communications systems. Early life, education and career Gordon Welchman was born, the youngest of three children, at Fishponds in Bristol, to William Welchman (1866–1954) and Elizabeth Marshall Griffith. William was a Church of England priest who had been a missionary overseas before returning to England as a country vicar, eventually becoming archdeacon of Bristol. Elizabeth was the daughter of another priest, the Revd Edward Moule Griffith. Welchman was educated at Marlborough College and then studied mathematics at Trinity College, Cambridge, from 1925 to 1928. In 1929, he became a Research Fellow in Mathematics at Sidney Sussex College, Cambridge. He became a Fe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vacuum Tube
A vacuum tube, electron tube, valve (British usage), or tube (North America), is a device that controls electric current flow in a high vacuum between electrodes to which an electric potential difference has been applied. The type known as a thermionic tube or thermionic valve utilizes thermionic emission of electrons from a hot cathode for fundamental electronic functions such as signal amplification and current rectification. Non-thermionic types such as a vacuum phototube, however, achieve electron emission through the photoelectric effect, and are used for such purposes as the detection of light intensities. In both types, the electrons are accelerated from the cathode to the anode by the electric field in the tube. The simplest vacuum tube, the diode (i.e. Fleming valve), invented in 1904 by John Ambrose Fleming, contains only a heated electron-emitting cathode and an anode. Electrons can only flow in one direction through the device—from the cathode to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heath Robinson (codebreaking Machine)
Heath Robinson was a machine used by British codebreakers at the Government Code and Cypher School (GC&CS) at Bletchley Park during World War II in cryptanalysis of the Lorenz cipher. This achieved the decryption of messages in the German teleprinter cipher produced by the Lorenz SZ40/42 in-line cipher machine. Both the cipher and the machines were called "Tunny" by the codebreakers, who named different German teleprinter ciphers after fish. It was mainly an electro-mechanical machine, containing no more than a couple of dozen valves (vacuum tubes), and was the predecessor to the electronic Colossus computer. It was dubbed "Heath Robinson" by the Wrens who operated it, after cartoonist William Heath Robinson, who drew immensely complicated mechanical devices for simple tasks, similar to (and somewhat predating) Rube Goldberg in the U.S. The functional specification of the machine was produced by Max Newman. The main engineering design was the work of Frank Morrell at the Po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lorenz Cipher
The Lorenz SZ40, SZ42a and SZ42b were German rotor stream cipher machines used by the German Army during World War II. They were developed by C. Lorenz AG in Berlin. The model name ''SZ'' was derived from ''Schlüssel-Zusatz'', meaning ''cipher attachment''. The instruments implemented a Vernam stream cipher. British cryptanalysts, who referred to encrypted German teleprinter traffic as ''Fish'', dubbed the machine and its traffic ''Tunny'' (meaning tunafish) and deduced its logical structure three years before they saw such a machine. The SZ machines were in-line attachments to standard teleprinters. An experimental link using SZ40 machines was started in June 1941. The enhanced SZ42 machines were brought into substantial use from mid-1942 onwards for high-level communications between the German High Command in Wünsdorf close to Berlin, and Army Commands throughout occupied Europe. The more advanced SZ42A came into routine use in February 1943 and the SZ42B in June 1944. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptanalysis Of The Lorenz Cipher
Cryptanalysis of the Lorenz cipher was the process that enabled the British to read high-level German army messages during World War II. The British Government Code and Cypher School (GC&CS) at Bletchley Park decrypted many communications between the '' Oberkommando der Wehrmacht'' (OKW, German High Command) in Berlin and their army commands throughout occupied Europe, some of which were signed "Adolf Hitler, Führer". These were intercepted non- Morse radio transmissions that had been enciphered by the Lorenz SZ teleprinter rotor stream cipher attachments. Decrypts of this traffic became an important source of "Ultra" intelligence, which contributed significantly to Allied victory. For its high-level secret messages, the German armed services enciphered each character using various online ''Geheimschreiber'' (secret writer) stream cipher machines at both ends of a telegraph link using the 5-bit International Telegraphy Alphabet No. 2 (ITA2). These machines were subsequently d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Max Newman
Maxwell Herman Alexander Newman, FRS, (7 February 1897 – 22 February 1984), generally known as Max Newman, was a British mathematician and codebreaker. His work in World War II led to the construction of Colossus, the world's first operational, programmable electronic computer, and he established the Royal Society Computing Machine Laboratory at the University of Manchester, which produced the world's first working, stored-program electronic computer in 1948, the Manchester Baby. Education and early life Newman was born Maxwell Herman Alexander Neumann in Chelsea, London, England, to a Jewish family, on 7 February 1897. His father was Herman Alexander Neumann, originally from the German city of Bromberg (now in Poland), who had emigrated with his family to London at the age of 15.William Newman, "Max Newman – Mathematician, Codebreaker and Computer Pioneer", pp. 176–188 in Herman worked as a secretary in a company, and married Sarah Ann Pike, an Irish schoolteacher ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
