|
Cryptologist
This is a list of cryptographers. Cryptography is the practice and study of techniques for secure communication in the presence of third parties called adversaries. Pre twentieth century * Al-Khalil ibn Ahmad al-Farahidi: wrote a (now lost) book on cryptography titled the "''Book of Cryptographic Messages''". * Al-Kindi, 9th century Arabic polymath and originator of frequency analysis. * Athanasius Kircher, attempts to decipher crypted messages * Augustus the Younger, Duke of Brunswick-Lüneburg, wrote a standard book on cryptography * Ibn Wahshiyya: published several cipher alphabets that were used to encrypt magic formulas. * John Dee, wrote an occult book, which in fact was a cover for crypted text * Ibn 'Adlan: 13th-century cryptographer who made important contributions on the sample size of the frequency analysis. * Duke of Mantua Francesco I Gonzaga is the one who used the earliest example of homophonic Substitution cipher in early 1400s. * Ibn al-Durayhim: gave detailed d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ibn Al-Durayhim
ʿAlī ibn Muḥammad Ibn al-Durayhim ( ar, علي بن محمد ابن الدريهم; 1312–1359/62 CE) was an Arab cryptologist who gave detailed descriptions of eight cipher systems that discussed substitution ciphers, leading to the earliest suggestion of a "tableau" of the kind that two centuries later became known as the " Vigenère table". His book entitled ''Clear Chapters Goals and Solving Ciphers'' (مقاصد الفصول المترجمة عن حل الترجمة) was recently discovered, but has yet to be published. It includes the use of the statistical techniques pioneered by Al-Kindi and Ibn 'Adlan ʻAfīf al-Dīn ʻAlī ibn ʻAdlān al-Mawsilī ( ar, عفيف لدين علي بن عدلان الموصلي ; 1187–1268 CE), born in Mosul, was an Arab cryptologist, linguist and poet who is known for his early contributions to cryptanalysi .... References {{DEFAULTSORT:Ibn al-Durayhim 1312 births 14th-century deaths Pre-19th-century cryptographers Mathe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ibn 'Adlan
ʻAfīf al-Dīn ʻAlī ibn ʻAdlān al-Mawsilī ( ar, عفيف لدين علي بن عدلان الموصلي ; 1187–1268 CE), born in Mosul, was an Arab cryptologist, linguist and poet who is known for his early contributions to cryptanalysis, to which he dedicated at least two books. He was also involved in literature and poetry, and taught on the Arabic language at the Al-Salihiyya Mosque of Cairo. He was in contact with various rulers of his time, and in this capacity he gained practical experience in cryptanalysis or the science of breaking encoded messages. He dedicated ''On Cryptanalysis,'' his only surviving work on the topic'','' to Al-Ashraf Musa (), the Ayyubid Emir of Damascus. He wrote three other books, including ''Al-Mu'lam'' (''The Told ook'), also on cryptanalysis, but it is now lost. ''On Cryptanalysis'' is a sort of guidebook for cryptanalysts, containing twenty sets of techniques he calls "rules". The methods contains more practical details than Al-Kin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giovan Battista Bellaso
Giovan Battista Bellaso (Brescia 1505–...) was an Italian cryptologist. The Vigenère cipher is named after Blaise de Vigenère, although Giovan Battista Bellaso had invented it before Vigenère described his autokey cipher. Biography Bellaso was born of a distinguished family in 1505. His father was Piervincenzo, a patrician of Brescia, owner since the 15th century of a house in town and a suburban estate in Capriano, in a neighborhood called Fenili Belasi (Bellaso's barns), including the Holy Trinity chapel. The chaplain was remunerated each year with a regular salary, and a supply of firewood. The family coat of arms was ‘‘On a blue field three red-tongued gold lion heads in side view”. Bellaso received a degree in civil law at the University of Padua in 1538. The French author, Blaise de Vigenère, reported that he was serving as a secretary in the suite of Cardinal Rodolfo Pio di Carpi and credited him with the invention of the reciprocal table, now called the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyalphabetic Substitution
A polyalphabetic cipher substitution, using multiple substitution alphabets. The Vigenère cipher is probably the best-known example of a polyalphabetic cipher, though it is a simplified special case. The Enigma machine is more complex but is still fundamentally a polyalphabetic substitution cipher. History The work of Al-Qalqashandi (1355–1418), based on the earlier work of Ibn al-Durayhim (1312–1359), contained the first published discussion of the substitution and transposition of ciphers, as well as the first description of a polyalphabetic cipher, in which each plaintext letter is assigned more than one substitute. However, it has been claimed that polyalphabetic ciphers may have been developed by the Arab cryptologist Al Kindi (801–873) centuries earlier. The Alberti cipher by Leon Battista Alberti around 1467 was an early polyalphabetic cipher. Alberti used a mixed alphabet to encrypt a message, but whenever he wanted to, he would switch to a different alphabet, ind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptography
Cryptography, or cryptology (from grc, , translit=kryptós "hidden, secret"; and ''graphein'', "to write", or ''-logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adversarial behavior. More generally, cryptography is about constructing and analyzing protocols that prevent third parties or the public from reading private messages. Modern cryptography exists at the intersection of the disciplines of mathematics, computer science, information security, electrical engineering, digital signal processing, physics, and others. Core concepts related to information security ( data confidentiality, data integrity, authentication, and non-repudiation) are also central to cryptography. Practical applications of cryptography include electronic commerce, chip-based payment cards, digital currencies, computer passwords, and military communications. Cryptography prior to the modern age was effectively synonymo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arabic
Arabic (, ' ; , ' or ) is a Semitic languages, Semitic language spoken primarily across the Arab world.Semitic languages: an international handbook / edited by Stefan Weninger; in collaboration with Geoffrey Khan, Michael P. Streck, Janet C. E.Watson; Walter de Gruyter GmbH & Co. KG, Berlin/Boston, 2011. Having emerged in the 1st century, it is named after the Arabs, Arab people; the term "Arab" was initially used to describe those living in the Arabian Peninsula, as perceived by geographers from ancient Greece. Since the 7th century, Arabic has been characterized by diglossia, with an opposition between a standard Prestige (sociolinguistics), prestige language—i.e., Literary Arabic: Modern Standard Arabic (MSA) or Classical Arabic—and diverse vernacular varieties, which serve as First language, mother tongues. Colloquial dialects vary significantly from MSA, impeding mutual intelligibility. MSA is only acquired through formal education and is not spoken natively. It is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crimean War
The Crimean War, , was fought from October 1853 to February 1856 between Russia and an ultimately victorious alliance of the Ottoman Empire, France, the United Kingdom and Piedmont-Sardinia. Geopolitical causes of the war included the decline of the Ottoman Empire, the expansion of the Russian Empire in the preceding Russo-Turkish Wars, and the British and French preference to preserve the Ottoman Empire to maintain the balance of power in the Concert of Europe. The flashpoint was a disagreement over the rights of Christian minorities in Palestine, then part of the Ottoman Empire, with the French promoting the rights of Roman Catholics, and Russia promoting those of the Eastern Orthodox Church. The churches worked out their differences with the Ottomans and came to an agreement, but both the French Emperor Napoleon III and the Russian Tsar Nicholas I refused to back down. Nicholas issued an ultimatum that demanded the Orthodox subjects of the Ottoman Empire be placed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giovanni Fontana (engineer)
Giovanni Fontana, also known as Johannes de Fontana (ca. 1395 – ca. 1455) was a fifteenth-century Italian physician and engineer. He was born in Venice in the 1390s and attended the University of Padua, where he received his degree in arts in 1418 and his degree in medicine in 1421. University records list him as "Master John, son of Michael de la Fontana". His most famous promoter at the University was the scholastic Paul of Venice. He tells us that the Doge of Venice sent him to Brescia to deliver a message to the condottiere Francesco Carmagnola. He was also employed as the municipal physician by the city of Udine. Works Fontana composed treatises on a diverse array of topics, including measurement of heights or depths by falling stones. We have early works of his on water-clocks (with wheels), sand-clocks and measurement. Fontana studied trigonometric measurements, mentioned in ''De trigono balistario'', and through his own designed instrument, also explained in a larger tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adversary (cryptography)
In cryptography, an adversary (rarely opponent, enemy) is a malicious entity whose aim is to prevent the users of the cryptosystem from achieving their goal (primarily privacy, integrity, and availability of data). An adversary's efforts might take the form of attempting to discover secret data, corrupting some of the data in the system, spoofing the identity of a message sender or receiver, or forcing system downtime. Actual adversaries, as opposed to idealized ones, are referred to as ''attackers''. The former term predominates in the cryptographic and the latter in the computer security literature. Eve, Mallory, Oscar and Trudy are all adversarial characters widely used in both types of texts. This notion of an adversary helps both intuitive and formal reasoning about cryptosystems by casting security analysis of cryptosystems as a 'game' between the users and a ''centrally co-ordinated'' enemy. The notion of security of a cryptosystem is meaningful only with respect to parti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jefferson Disk
The Jefferson disk, also called the Bazeries Cylinder or wheel cypher as named by Thomas Jefferson, is a cipher system using a set of wheels or disks, each with the 26 letters of the alphabet arranged around their edge. The order of the letters is different for each disk and is usually ordered randomly. Each disk is marked with a unique number and a hole in the center of the disks allows them to be stacked on an axle. The disks are removable and can be mounted on the axle in any order desired. The order of the disks is the cipher key, and both sender and receiver must arrange the disks in the same predefined order. Jefferson's device had 36 disks.Kahn, p. 194 Once the disks have been placed on the axle in the agreed order, the sender rotates each disk up and down until a desired message is spelled out in one row. Then, the sender can copy down any row of text on the disks other than the one that contains the plaintext message. The recipient has to arrange the disks in the agreed- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Étienne Bazeries
Étienne Bazeries (21 August 1846, in Port Vendres – 7 November 1931, in Noyon) was a French military cryptanalyst active between 1890 and the First World War. He is best known for developing the " Bazeries Cylinder", an improved version of Thomas Jefferson's cipher cylinder. It was later refined into the US Army M-94 cipher device. Historian David Kahn describes him as "''the great pragmatist of cryptology. His theoretical contributions are negligible, but he was one of the greatest natural cryptanalysts the science has seen.''" (Kahn 1996, p244) Bazeries was born in Port-Vendres, France, the son of a mounted policeman. In 1863 he enlisted in the army, and fought in the Franco-Prussian War, where he was taken prisoner, although he later managed to escape disguised as a bricklayer. In 1874 he was promoted to lieutenant, and sent to Algeria in 1875. He returned to France the following year and married Marie-Louise-Elodie Berthon, with whom he would father three daughters: Cé ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptanalysis
Cryptanalysis (from the Greek ''kryptós'', "hidden", and ''analýein'', "to analyze") refers to the process of analyzing information systems in order to understand hidden aspects of the systems. Cryptanalysis is used to breach cryptographic security systems and gain access to the contents of encrypted messages, even if the cryptographic key is unknown. In addition to mathematical analysis of cryptographic algorithms, cryptanalysis includes the study of side-channel attacks that do not target weaknesses in the cryptographic algorithms themselves, but instead exploit weaknesses in their implementation. Even though the goal has been the same, the methods and techniques of cryptanalysis have changed drastically through the history of cryptography, adapting to increasing cryptographic complexity, ranging from the pen-and-paper methods of the past, through machines like the British Bombes and Colossus computers at Bletchley Park in World War II, to the mathematically advanced comput ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
_Johannes_de_Fontana_Bellicorum_instrumentorum_liber_cum_figuris.jpg "Click for more on -> Giovanni Fontana (engineer)")