History of cryptography and cryptanalysis pdf Continue Aspect of history This article may contain original research. Please improve it by checking the claims made and adding links. Applications consisting only of original research must be removed. (January 2018) (Learn how and when to delete this template message) Cryptography, the use of codes and ciphers to protect secrets, began thousands of years ago. Until recent decades, it was a story about what might be called classical cryptography - that is, encryption techniques that use pen and paper, or perhaps simple mechanical means. In the early 20th century, the invention of sophisticated mechanical and electromechanical machines, such as the Enigma rotary machine, provided more sophisticated and efficient encryption tools; and the subsequent introduction of electronics and computing has allowed for the development of more complex circuits, most of which are completely unprocessed for pen and paper. In parallel with the development of cryptography is the development of cryptoanalysis - hacking codes and ciphers. Detection and application, early on, frequency analysis to read encrypted messages, sometimes changed the course of history. Thus, the telegram provoked the United States to enter World War I; and allied reading of the ciphers of Nazi Germany shortening world war II, in some estimates as much as two years. Until the 1960s, safe cryptography was largely the prerogative of governments. Two events have since brought him directly into the public domain: the creation of the Public Encryption Standard (DES), and the invention of public key cryptography. Ancient Scytale, an early device for encryption. The earliest known use of cryptography is found in non-standard hieroglyphics carved into the wall of the tomb from the Old Kingdom of Egypt around 1900 BC However, these are not serious attempts of secret messages, but attempts of riddles, intrigues or even entertainment for literate viewers. Some clay tablets from Mesopotamia are somewhat later explicitly intended to protect information - one from around 1500 BC was found to encrypt the artisan's recipe for pottery glaze, presumably commercially valuable. In addition, Jewish scientists used simple monoalfabetic replacement ciphers (such as the Atbash cipher) starting, perhaps from about 600 BC to 500 BC, in India around 400 BC to 200 AD, Mlecchita vikalpa or the art of understanding writing in cipher, and the spelling of words was specially documented in Kama Sutra with the aim of communicating between lovers. It's also probably a simple replacement cipher. Parts of the Egyptian demotic Greek magical papiri were written with a cipher. The ancient Greeks are said to know the ciphers. Scytale transposition cipher was Spartan military, but it is not known definitively whether there was a scytale for encryption, authentication or avoiding bad omens in speech. Herodotus tells us about secret messages physically hidden under wax on wooden plates or as a tattoo on a slave's head, hidden from outgrown hairs, although they are not properly examples of cryptography per se, since the message is only known to be read directly; it's known as steganography. Another Greek method was developed by Polybius (now called Polybius Square). The Romans knew something about cryptography (such as Caesar's cipher and its variations). Medieval cryptography The first page of al-Kindi's manuscript on cryptographic messages, containing the first descriptions of cryptoanalysis and frequency analysis. See also: The classic cipher and manuscript of Voynich David Kahn notes in Codebreakers that modern cryptology originated among Arabs, the first people to systematically document cryptoanalytic methods. Al-Khalil (717-786) wrote the Book of Cryptographic Messages, which contains the first use of permutations and combinations to list all possible Arabic words with and without vowels. The invention of the frequency analysis method to crack monoalfabetic ciphers replacing Al-Kindi, an Arab mathematician, around 800 AD, proved to be the most significant crypto-analytical progress before World War II. Al-Kindi wrote a book on cryptography called Risalah fi Istikhraj al-Mu'amma (Manuscript for the Decipheric Messages), in which he described the first cryptoanalytic methods, including polyalphabetic ciphers, cipher classification, Arabic phonetics and syntax, and most importantly, gave the first descriptions on frequency analysis. It also covered methods of enciference, cryptoanalysis of some bonds and statistical analysis of letters and combinations of letters in Arabic. An important contribution by Ibn Adlan (1187-1268) was the sample size for the use of frequency analysis. In early medieval England, between 800 and 1100, replacement ciphers were often used by scribes as a playful and clever way of entangling notes, puzzles and colophons. The ciphers are usually quite simple, but sometimes they deviate from the usual pattern, adding to their complexity, and perhaps also to their complexity. During this period, the West had vital and significant cryptographic experiments. Ahmad al-Allkashandi (1355-1418) wrote Subh al-Sha, a 14-volume encyclopedia that included a section on cryptology. This information was attributed to Ibn al-Durayhimu, who lived from 1312 AD to 1361, but whose cryptography work was lost. The list of ciphers in this work included both substitution and transposition and a cipher with multiple substitutions for each letter of simple text (later called homophonic replacement). Also traced Ibn al-Durayhim is an exposition and worked an example of cryptoanalysis, including the use of tables of letter frequencies and sets of letters that can not happen together in one word. The earliest example of the homophonic replacement cipher is the cipher used by the Duke of Mantua in the early 1400s. The cipher is ahead of time because it combines monoalfabetic and polyalphabetic features. Essentially, all ciphers remained vulnerable to the cryptoanalytic technique of frequency analysis until the development of polyalphabet cipher, and many remained so after that. The polyalphabetic cipher was most clearly explained by Leon Battista Alberti around 1467 AD, for which he was called the father of Western cryptology. Johannes Tritemius in his work Polygraphia invented the tabula recta, the most important component of the cipher Vigener. Trithemium also wrote a steganography. French cryptographer Blaise de Vigener developed a practical polyalphabetic system that bears his name, the Cipher Cigener. In Europe, cryptography has become (secretly) more important as a result of political competition and religious revolution. For example, in Europe during and after the Renaissance, citizens of various Italian states, including the pontifical states and the Roman Catholic Church, were responsible for the rapid spread of cryptographic methods, few of which reflected the understanding (or even knowledge) of Alberti's polyalphabetic progression. Advanced ciphers, even after Alberti, were not as advanced as their inventors/developers/users claimed (and probably even they themselves believed). They often broke down. This over- optimism may be inherent in cryptography, because it was then - and remains today - difficult in principle to know how vulnerable your own system is. In the absence of knowledge, guesswork and hope are predictably common. Cryptography, cryptanalysis and betrayal of the secret agent/courier were featured in The Babington story during the reign of queen Elizabeth I, which led to the execution of Mary, queen of Scotland. Robert Hook suggested in the chapter of Dr. Dee's Book of Spirits that John Dee used triteian steganography to hide his communication with queen Elizabeth I. He and his family created what is known as the Great Cipher because it remained unresolved from its original use until 1890, when the French military cryptoanalyst Etienne Baseri decided it. The encrypted message of the times of the Man in the Iron Mask (deciphered shortly before 1900 by Etienne Bazeri) shed some, unfortunately, neo-icom light on the the personality of this real, if legendary and unhappy, prisoner. Outside Europe, after the Mongols brought the End of the Islamic Golden Age to an end, cryptography remained relatively undeveloped. Cryptography in Japan does not seem to have been used until about 1510, and advanced methods were not known until after the discovery of the country in the West, dating back to the 1860s. Cryptography from 1800 to World War II Home article: World War I cryptography Although cryptography has a long and complex history, it was not until the 19th century that it developed nothing more than special approaches to encryption or cryptoanalysis (the science of finding weaknesses in cryptosystems). Examples include Charles Babbig's work of the Crimean War era on the mathematical cryptoanalysis of polyalphabetic ciphers, reworked and published a little later by Prussian Friedrich Kasischi. Understanding cryptography at this time usually consisted of having a hard time winning the rules of the thumb; see, for example, the cryptographic works of Augustin Kerkhoff in the 19th century. Edgar Allan Poe used systematic methods to solve ciphers in the 1840s. Specifically, he posted a notice of his abilities in the Philadelphia newspaper Alexander's Weekly (Express) Messenger, inviting him to submit ciphers, of which he began to address almost all. Its success has caused a public outcry for months. He later wrote an essay on cryptography techniques that proved