Timeline 1900-1970 AD 1913 the wheel cipher gets re-invented as a strip 1917 William Frederick Friedman starts working as a cryptoanalyst at Riverbank Laboratories, which also works for the U.S. Government. Later he creates a school for military cryptoanalysis - an AT&T-employee, Gilbert S. Vernam, invents a polyalphabetic cipher machine that works with random-keys 1918 the Germans start using the ADFGVX-system, that later gets later by the French Georges Painvin - Arthur Scherbius patents a ciphering machine and tries to sell it to the German Military, but is rejected 1919 Hugo Alexander Koch invents a rotor cipher machine 1921 the Hebern Electric Code, a company producing electro-mechanical cipher machines, is founded 1923 Arthur Scherbius founds an enterprise to construct and finally sell his Enigma machine for the German Military late 1920's/30's more and more it is criminals who use cryptology for their purposes (e.g. for smuggling). Elizabeth Smith Friedman deciphers the codes of rum-smugglers during prohibition regularly 1929 Lester S. Hill publishes his book Cryptography in an Algebraic Alphabet, which contains enciphered parts 1933-1945 the Germans make the Enigma machine its cryptographic main-tool, which is broken by the Poles Marian Rejewski, Gordon Welchman and Alan Turing's team at Bletchley Park in England in 1939 1937 the Japanese invent their so called Purple machine with the help of Herbert O. Yardley. The machine works with telephone stepping relays. It is broken by a team of William Frederick Friedman. As the Japanese were unable to break the US codes, they imagined their own codes to be unbreakable as well - and were not careful enough. 1930's the Sigaba machine is invented in the USA, either by W.F. Friedman or his colleague Frank Rowlett - at the same time the British develop the Typex machine, similar to the German Enigma machine 1943 Colossus, a code breaking computer is put into action at Bletchley Park 1943-1980 the cryptographic Venona Project, done by the NSA, is taking place for a longer period than any other program of that type 1948 Shannon, one of the first modern cryptographers bringing mathematics into cryptography, publishes his book A Communications Theory of Secrecy Systems 1960's the Communications-Electronics Security Group (= CESG) is founded as a section of Government Communications Headquarters (= GCHQ) late 1960's the IBM Watson Research Lab develops the Lucifer cipher 1969 James Ellis develops a system of separate public-keys and private-keys

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Timeline of Communication Systems: Introduction The timeline of communication systems presents a chronological overview of the most important events in the history of communication systems from the 4th millennium B.C. to the present. It shows that from the very beginning - the first Sumerian pictographs on clay tablets to today's state-of-the-art technologies - broadband communication via fiber-optic cables and satellites - the amount of information collected, processed and stored, the capabilities to do so, as well as the capable speed of information transmission exponentially accelerate.

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Moral rights Authors of copyrighted works (besides economic rights) enjoy moral rights on the basis of which they have the right to claim their authorship and require that their names be indicated on the copies of the work and in connection with other uses thereof. Moral rights are generally inalienable and remain with the creator even after he has transferred his economic rights, although the author may waive their exercise.

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Expert system Expert systems are advanced computer programs that mimic the knowledge and reasoning capabilities of an expert in a particular discipline. Their creators strive to clone the expertise of one or several human specialists to develop a tool that can be used by the layman to solve difficult or ambiguous problems. Expert systems differ from conventional computer programs as they combine facts with rules that state relations between the facts to achieve a crude form of reasoning analogous to artificial intelligence. The three main elements of expert systems are: (1) an interface which allows interaction between the system and the user, (2) a database (also called the knowledge base) which consists of axioms and rules, and (3) the inference engine, a computer program that executes the inference-making process. The disadvantage of rule-based expert systems is that they cannot handle unanticipated events, as every condition that may be encountered must be described by a rule. They also remain limited to narrow problem domains such as troubleshooting malfunctioning equipment or medical image interpretation, but still have the advantage of being much lower in costs compared with paying an expert or a team of specialists.

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Artificial Intelligence Artificial Intelligence is concerned with the simulation of human thinking and emotions in information technology. AI develops "intelligent systems" capable, for example, of learning and logical deduction. AI systems are used for creatively handling large amounts of data (as in data mining), as well as in natural speech processing and image recognition. AI is also used as to support decision taking in highly complex environments. Yahoo AI sites: http://dir.yahoo.com/Science/Computer_Science/Artificial_Intelligence/ MIT AI lab: http://www.ai.mit.edu/ http://dir.yahoo.com/Science/Computer_Science... http://www.ai.mit.edu/

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