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In cryptography, a substitution cipher is a method of encryption by which units of plaintext are replaced with ciphertext, according to a regular system ; the " units " may be single letters ( the most common ), pairs of letters, triplets of letters, mixtures of the above, and so forth.
Some Related Sentences
cryptography and substitution
Poe's success in cryptography relied not so much on his knowledge of that field ( his method was limited to the simple substitution cryptogram ), as on his knowledge of the magazine and newspaper culture.
In classical cryptography, one of the earliest encryption methods was the simple substitution cipher, where letters in a message were systematically replaced using some secret scheme.
In cryptography, an S-Box ( Substitution-box ) is a basic component of symmetric key algorithms which performs substitution.
The story involves cryptography with a detailed description of a method for solving a simple substitution cipher using letter frequencies.
In classical cryptography, the running key cipher is a type of polyalphabetic substitution cipher in which a text, typically from a book, is used to provide a very long keystream.
In classical cryptography, the Hill cipher is a polygraphic substitution cipher based on linear algebra.
cryptography and cipher
In cryptography, a block cipher is a deterministic algorithm operating on fixed-length groups of bits, called blocks, with an unvarying transformation that is specified by a symmetric key.
In cryptography, a cipher ( or cypher ) is an algorithm for performing encryption or decryption — a series of well-defined steps that can be followed as a procedure.
In non-technical usage, a " cipher " is the same thing as a " code "; however, the concepts are distinct in cryptography.
In cryptography, key size or key length is the size measured in bits of the key used in a cryptographic algorithm ( such as a cipher ).
In cryptography, encryption is the process of transforming information ( referred to as plaintext ) using an algorithm ( called a cipher ) to make it unreadable to anyone except those possessing special knowledge, usually referred to as a key.
In cryptography, the International Data Encryption Algorithm ( IDEA ) is a block cipher designed by James Massey of ETH Zurich and Xuejia Lai and was first described in 1991.
The polyalphabetic cipher was, at least in principle, for it was not properly used for several hundred years, the most significant advance in cryptography since before Julius Caesar's time.
* MARS ( cryptography ), a block cipher that was IBM's submission to the Advanced Encryption Standard process.
In cryptography, RC4 ( also known as ARC4 or ARCFOUR meaning Alleged RC4, see below ) is the most widely used software stream cipher and is used in popular protocols such as Secure Sockets Layer ( SSL ) ( to protect Internet traffic ) and WEP ( to secure wireless networks ).
The term cypherpunk, derived from cipher and punk, was coined by Jude Milhon as a pun to describe cyberpunks who used cryptography.
In the history of cryptography, Typex ( alternatively, Type X or TypeX ) machines were British cipher machines used from 1937.
In cryptography, a transposition cipher is a method of encryption by which the positions held by units of plaintext ( which are commonly characters or groups of characters ) are shifted according to a regular system, so that the ciphertext constitutes a permutation of the plaintext.
In other words, two successive applications of ROT13 restore the original text ( in mathematics, this is sometimes called an involution ; in cryptography, a reciprocal cipher ).
In cryptography, Triple DES is the common name for the Triple Data Encryption Algorithm ( TDEA or Triple DEA ) block cipher, which applies the Data Encryption Standard ( DES ) cipher algorithm three times to each data block.
In cryptography, a Caesar cipher, also known as Caesar's cipher, the shift cipher, Caesar's code or Caesar shift, is one of the simplest and most widely known encryption techniques.
In cryptography, a stream cipher is a symmetric key cipher where plaintext digits are combined with a pseudorandom cipher digit stream ( keystream ).
As with other attacks in cryptography, stream cipher attacks can be certificational, meaning they aren't necessarily practical ways to break the cipher but indicate that the cipher might have other weaknesses.
cryptography and is
The latter is more cumbersome to use, so it's only employed when necessary, for example in the analysis of arbitrary-precision arithmetic algorithms, like those used in cryptography.
* symmetric key algorithms ( Private-key cryptography ), where the same key is used for encryption and decryption, and
It is one of the earliest practical examples of key exchange implemented within the field of cryptography.
The introduction of DES is considered to have been a catalyst for the academic study of cryptography, particularly of methods to crack block ciphers.
" An astonishing share of the open literature in cryptography in the 1970s and 1980s dealt with the DES, and the DES is the standard against which every symmetric key algorithm since has been compared.
Elliptic curve cryptography ( ECC ) is an approach to public-key cryptography based on the algebraic structure of elliptic curves over finite fields.
Elliptic curve cryptography is vulnerable to a modified Shor's algorithm for solving the discrete logarithm problem on elliptic curves.
Factorization of large integers is believed to be a computationally very difficult problem, and the security of many modern cryptography systems is based upon its infeasibility.
The Communications-Electronics Security Group ( CESG ) of GCHQ provides assistance to government departments on their own communications security: CESG is the UK national technical authority for information assurance, including cryptography.
Although related, the distinctions among these measures mean that a random variable with high Shannon entropy is not necessarily satisfactory for use in an extractor and so for cryptography uses.
Information security uses cryptography to transform usable information into a form that renders it unusable by anyone other than an authorized user ; this process is called encryption.
The presumed difficulty of this problem is at the heart of widely used algorithms in cryptography such as RSA.
The problem often arises in resource allocation where there are financial constraints and is studied in fields such as combinatorics, computer science, complexity theory, cryptography and applied mathematics.
cryptography and method
The method was followed shortly afterwards by RSA, an implementation of public key cryptography using asymmetric algorithms.
During the early history of cryptography, two parties would rely upon a key using a secure, but non-cryptographic, method.
Although sequences that are closer to truly random can be generated using hardware random number generators, pseudorandom numbers are important in practice for their speed in number generation and their reproducibility, and they are thus central in applications such as simulations ( e. g., of physical systems with the Monte Carlo method ), in cryptography, and in procedural generation.
Lagrange polynomials are used in the Newton – Cotes method of numerical integration and in Shamir's secret sharing scheme in cryptography.
In traditional symmetric key cryptography, this problem wasn't an issue as it was implicitly assumed that some " secure " method of key distribution guaranteed key authenticity.
It introduced a radically new method of distributing cryptographic keys, which went far toward solving one of the fundamental problems of cryptography, key distribution.
It introduced a radically new method of distributing cryptographic keys, that went far toward solving one of the fundamental problems of cryptography, key distribution.
In cryptography, a zero-knowledge proof or zero-knowledge protocol is an interactive method for one party to prove to another that a ( usually mathematical ) statement is true, without revealing anything other than the veracity of the statement.
This fabrication method has potential for applications in quantum cryptography ( i. e. single photon sources ) and quantum computation.
Key exchange ( also known as " key establishment ") is any method in cryptography by which cryptographic keys are exchanged between users, allowing use of a cryptographic algorithm.
In cryptography, Russian copulation is a method of rearranging plaintext before encryption so as to conceal stereotyped headers, salutations, introductions, endings, signatures, etc.
* An asymmetric-key cryptosystem is published by Whitfield Diffie and Martin Hellman who disclose the Diffie – Hellman key exchange method of public-key agreement for public-key cryptography.
Clark Stanley's Snake Oil. In cryptography, snake oil is any commercial cryptographic method or product considered to be bogus or fraudulent.
Shortly afterward, Netscape's SSL technology was widely adopted as a method for protecting credit card transactions using public key cryptography.
In cryptology, cryptography is a method used to transform a message into an obscured form so it cannot be understood.
* The method for changing between polynomial and normal bases, and similar transformations, for purposes of coding theory and cryptography.
In cryptography, ciphertext stealing ( CTS ) is a general method of using a block cipher mode of operation that allows for processing of messages that are not evenly divisible into blocks without resulting in any expansion of the ciphertext, at the cost of slightly increased complexity.
The main use of the tables was in statistics and the experimental design of scientific experiments, especially those that used the Monte Carlo method ; in cryptography, they have also been used as nothing up my sleeve numbers, for example in the design of the Khafre cipher.