Reja Kirish II. Asosiy qism Jeferson kriptografik shifrlash qurilmasi. Uning ishlash prinspi Hagelin m-209 kriptografik shifrlash qurilmasi haqida umumiy tushunchalar. Enigma shifrlash qurilmasi. Shifrlash jarayonida bajaradigan algoritm
Enigma shifrlash qurilmasi. Shifrlash jarayonida bajaradigan algoritm
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2.3. Enigma shifrlash qurilmasi. Shifrlash jarayonida bajaradigan algoritm. The history of the Enigma starts around 1915, with the invention of the rotor-based cipher machine. As usual in history, the rotor machine was invented more or less simultaneously in different parts of the world. In 1917 there were inventions from Edward Hebern in the USA, Arvid Damm in Sweden, Hugo Koch in The Netherlands and Arthur Scherbius in Germany [1]. The inventors of the rotor machine, from left to right: Theo van Hengel, Edward Hebern and Arthur Scherbius.
Officially though, the Enigma machine was invented by Arthur Scherbius in 1918, right at the end of World War I. After several years of improving his invention, the first machine saw the light of day in 1923. A year earlier he had secured the rights to patent NL10700 of Dutch inventor Hugo Koch for a similar device [4]. It was a rather large typewriter-style machine that was developed by Scherbius' first company Scherbius & Ritter of Berlin-Wansee (Germany), but was built by Gewerkschaft Securitas (later: Chiffriermaschinen AG), also of Berlin. This machine was known as Die Handelsmaschine. As the machine prints its output directly on a sheet of paper (like a typewriter), it was also known as Schreibende Enigma (printing Enigma). It was first described in a technical article by Scherbius himself in 1923 [5]. As far as we know, none of the early Handelsmaschinen has survived. It was succeeded a year later by the Die schreibende Enigma, that had an improved printing mechanism. Glowlamp Enigma (1924)
For this reason, Scherbius developed a machine that produced its output on a lamp panel rather than on paper. The first model was the Enigma A that was introduced in 1924. It was also known as Gluhlampenmaschine (glow lamp machine). The machine was available for about 1/8th of the price of the printing Enigma and costed RM 1000 1 . The machine is housed in a wooden case and looks pretty much like the later Enigma models, except that the keys are arranged in sequential order (ABCDE...) rather than the more common typewriter order (QWERTZ...). The standard Enigma C has 26 keys (A-Z) for the input and 26 lamps (A-Z) for the output. The text is scrambled by means of three cipher wheels that protrude the top lid. Each cipher wheel has 26 contacts at either side. Several variants of the Enigma C were produced, such as the so-called Funkschlüssel C (for the German Navy) and a Swedisch variant, both with 28 keys. The currency in Germany in 1924 was the Reichsmark (RM).
In 1926, the design of the glow lamp Enigma was drastically improved. A new chassis was developed and the standard (German) keyboard layout (QWERTZ...) was introduced. Furthermore the reflector (UKW) could be set to 26 different positions. It was mounted to the left of the three cipher wheels, which is why this machine is sometimes thought to be a 4-wheel Enigma. The machine was internally known as model A26 and became known as the Enigma D. Like the Enigma C it was housed in a wooden transit case with a hinged lid. It had several improvements. A lamp lights up when a key is pressed The wheels could be accessed more easily (i.e. the top lid could be opened), there was an optional sunlight filter for the lamp panel, and it had a power selector that was mounted to the right of the cipher wheels. The Enigma D became the basis for most of the later machines.
Enigmaning shifrlash qurilmasi quyidagi rasmda tasvirlangan. 3-rasm.Enigma kriptografik shifrlash qurilmasi. Enigmaning shifrlash usuli quyidagi rasmda berilgan.
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