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Rail Fence
The rail fence cipher (also called a zigzag cipher) is a classical type of transposition cipher. It derives its name from the manner in which encryption is performed, in analogy to a fence built with horizontal rails. Encryption In the rail fence cipher, the plaintext is written downwards diagonally on successive "rails" of an imaginary fence, then moving up when the bottom rail is reached, down again when the top rail is reached, and so on until the whole plaintext is written out. The ciphertext is then read off in rows. For example, to encrypt the message 'WE ARE DISCOVERED. RUN AT ONCE.' with 3 "rails", write the text as: W . . . E . . . C . . . R . . . U . . . O . . . . E . R . D . S . O . E . E . R . N . T . N . E . . A . . . I . . . V . . . D . . . A . . . C . (Spaces and punctuation are omitted.) Then read off the text horizontally to get the ciphertext: WECRUO ERDSOEERNTNE AIVDAC Decryption Let N be the number of rails used during encryption. Observe that as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Valla De Tablones
Valla is both a surname and place name which may refer to: * Valla (surname) Places * Valla (Dhaalu Atoll), an uninhabited island of the Maldives * Valla (Pieria), a town of ancient Pieria, Macedonia, Greece * Valla, Norway in Vega Municipality in Nordland county, Norway * Vallsjøen (Valla) in Meløy Municipality in Nordland county, Norway * Valla, New South Wales, a village in New South Wales, Australia * Valla, Sweden, locality situated in Katrineholm Municipality, Södermanland County, Sweden * Valla, locality in Linköping Municipality, Östergötland County, Sweden ** East Valla ** West Valla ** Valla Wood, nature reserve in the municipality of Linköping * Stora Valla, multi-use stadium in Degerfors, Sweden Other * Plural for Vallum, the whole or a portion of the fortifications of a Roman camp *Valla, a player character in the video game ''Heroes of the Storm'' See also * Valle (other) Valle may refer to: * Valle (surname) Geography *"Valle", the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Classical Cipher
In cryptography, a classical cipher is a type of cipher that was used historically but for the most part, has fallen into disuse. In contrast to modern cryptographic algorithms, most classical ciphers can be practically computed and solved by hand. However, they are also usually very simple to break with modern technology. The term includes the simple systems used since Greek and Roman times, the elaborate Renaissance ciphers, World War II cryptography such as the Enigma machine and beyond. In contrast, modern strong cryptography relies on new algorithms and computers developed since the 1970s. Types of classical ciphers Classical ciphers are often divided into ''transposition ciphers'' and ''substitution ciphers'', but there are also '' concealment ciphers''. Substitution ciphers In a substitution cipher, letters, or groups of letters, are systematically replaced throughout the message for other letters, groups of letters, or symbols. A well-known example of a substitution c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transposition Cipher
In cryptography, a transposition cipher (also known as a permutation cipher) is a method of encryption which scrambles the positions of characters (''transposition'') without changing the characters themselves. Transposition ciphers reorder units of plaintext (typically characters or groups of characters) according to a regular system to produce a ciphertext which is a permutation of the plaintext. They differ from Substitution cipher, substitution ciphers, which do not change the position of units of plaintext but instead change the units themselves. Despite the difference between transposition and substitution operations, they are often combined, as in historical ciphers like the ADFGVX cipher or complex high-quality encryption methods like the modern Advanced Encryption Standard (AES). General principle Plaintexts can be rearranged into a ciphertext using a Key (cryptography), key, scrambling the order of characters like the shuffled pieces of a jigsaw puzzle. The resulting m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brute-force Attack
In cryptography, a brute-force attack or exhaustive key search is a cryptanalytic attack that consists of an attacker submitting many possible keys or passwords with the hope of eventually guessing correctly. This strategy can theoretically be used to break any form of encryption that is not information-theoretically secure. However, in a properly designed cryptosystem the chance of successfully guessing the key is negligible. When cracking passwords, this method is very fast when used to check all short passwords, but for longer passwords other methods such as the dictionary attack are used because a brute-force search takes too long. Longer passwords, passphrases and keys have more possible values, making them exponentially more difficult to crack than shorter ones due to diversity of characters. Brute-force attacks can be made less effective by obfuscating the data to be encoded making it more difficult for an attacker to recognize when the code has been cracked or by ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aegean Park Press
Aegean Park Press was a publisher based in Walnut Creek, California, specializing in cryptology, military intelligence, contract bridge and Mayan languages. The company's books on cryptology were "mostly reprints of fairly advanced texts, " cluding at least 16 books by World War II cryptologists William F. Friedman, Lambros D. Callimahos, and Solomon Kullback. It published more than 50 books related to cryptology and a smaller number of books on other areas such as military intelligence." It did most of its business by direct mail. It was founded in 1973 by Wayne Barker (1922-2001). One of the company's ostensible customers has reported that it "ceased to exist either in lat 2011 or early 2012". Better Business Bureau The Better Business Bureau (BBB) is an American private, 501(c)(6) nonprofit organization founded in 1912. BBB's self-described mission is to focus on advancing marketplace trust, consisting of 92 independently incorporated local BBB organizati ... reported i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scytale
In cryptography, a scytale (; also transliterated skytale, ''skutálē'' "baton, cylinder", also ''skútalon'') is a tool used to perform a transposition cipher, consisting of a cylinder with a strip of parchment wound around it on which is written a message. The ancient Greeks, and the Sparta Sparta was a prominent city-state in Laconia in ancient Greece. In antiquity, the city-state was known as Lacedaemon (), while the name Sparta referred to its main settlement in the Evrotas Valley, valley of Evrotas (river), Evrotas rive ...ns in particular, are said to have used this cipher to communicate during military campaigns. The recipient uses a rod of the same diameter on which the parchment is wrapped to read the message. Encrypting Suppose the rod allows one to write four letters around in a circle and five letters down the side of it. The plaintext could be: "I am hurt very badly help". To encrypt, one simply writes across the leather: ________________________ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helen Fouché Gaines
Helen Fouché Gaines (October 12, 1888 – April 2, 1940) was a member of the American Cryptogram Association and editor of the book ''Cryptanalysis'' (originally ''Elementary Cryptanalysis'') first published in 1939. The book described the principal cryptographic systems of the 19th century and cracking methods including elementary contact analysis (cryptanalysis). Her pen name A pen name or nom-de-plume is a pseudonym (or, in some cases, a variant form of a real name) adopted by an author and printed on the title page or by-line of their works in place of their real name. A pen name may be used to make the author's na ... was PICCOLA. Shortly after the publication of the book, she died. Publications * References External links ACA history of the book from ''The ACA and you'' [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
