# Block cipher/Related Articles

From Citizendium, the Citizens' Compendium

*See also changes related to Block cipher, or pages that link to Block cipher or to this page or whose text contains "Block cipher".*

## Parent topics

- Cryptography [r]: A field at the intersection of mathematics and computer science that is concerned with the security of information, typically the confidentiality, integrity and authenticity of some message.
^{[e]} - Information security [r]: The set of policies and protective measures used to ensure appropriate confidentiality, integrity and availability to information; usually assumed to be information in a computer or telecommunications network but the principles extend to people and the physical world
^{[e]} - Cipher [r]: A means of combining plaintext (of letters or numbers, or bits), using an algorithm that mathematically manipulates the individual elements of plaintext, into ciphertext, a form unintelligible to any recipient that does not know both the algorithm and a randomizing factor called a cryptographic key
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## Subtopics

See our table of block ciphers for links to individual ciphers.

- Avalanche (cryptography) [r]: A desirable property for operations in a cipher or hash, where a small change (even a single bit) quickly builds up to creating large effects.
^{[e]} - Round (cryptography) [r]: A relatively simple operation which, when repeated many times, can be used to build an iterated cipher or hash.
^{[e]} - S-box (cryptography) [r]: A substitution box or lookup table.
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- Cryptanalysis [r]: The sub-field of cryptology which deals with breaking into existing codes and ciphers.
^{[e]} - Block cipher modes of operation [r]: Methods of combining multiple block cipher operations to achieve a larger goal.
^{[e]} - Hash (cryptography) [r]: An algorithm that produces a fixed-size digest from an input of essentially arbitrary size.
^{[e]} - Key (cryptography) [r]: Characteristics and generation of data which, in combination with a cryptographic algorithm, introduces or removes the concealment applied to plaintext or taken to ciphertext; key management is arelated but separate discipline of secure distribution of keys and entering them into cryptosystems
^{[e]} - Key management (cryptography) [r]:
*Add brief definition or description* - Stream cipher [r]: A cipher that encrypts data by mixing it with the output of a pseudorandom number generator controlled by a key; to decrypt, run the same generator with the same key to get the same pseudorandom data, then reverse the mixing step.
^{[e]} - Permutation cipher [r]:
*Add brief definition or description* - Transposition cipher [r]:
*Add brief definition or description*