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In cryptography, SHA-1 is a hash function which takes an input and produces a 160-bit (20-byte) hash value known as a message digest – typically rendered as 40 hexadecimal digits. It was designed by the United States National Security Agency, and is a U.S. Federal Information Processing Standard. The algorithm has been cryptographically broken but is still widely used.
A key in cryptography is a piece of information, usually a string of numbers or letters that are stored in a file, which, when processed through a cryptographic algorithm, can encode or decode cryptographic data. Based on the used method, the key can be different sizes and varieties, but in all cases, the strength of the encryption relies on the security of the key being maintained. A key's security strength is dependent on its algorithm, the size of the key, the generation of the key, and the process of key exchange.
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The following outline is provided as an overview of and topical guide to cryptography:
In cryptography, a sponge function or sponge construction is any of a class of algorithms with finite internal state that take an input bit stream of any length and produce an output bit stream of any desired length. Sponge functions have both theoretical and practical uses. They can be used to model or implement many cryptographic primitives, including cryptographic hashes, message authentication codes, mask generation functions, stream ciphers, pseudo-random number generators, and authenticated encryption.
NIST SP 800-90A is a publication by the National Institute of Standards and Technology with the title Recommendation for Random Number Generation Using Deterministic Random Bit Generators. The publication contains the specification for three allegedly cryptographically secure pseudorandom number generators for use in cryptography: Hash DRBG, HMAC DRBG, and CTR DRBG. Earlier versions included a fourth generator, Dual_EC_DRBG. Dual_EC_DRBG was later reported to probably contain a kleptographic backdoor inserted by the United States National Security Agency (NSA).
Hash-based cryptography is the generic term for constructions of cryptographic primitives based on the security of hash functions. It is of interest as a type of post-quantum cryptography.
References
- ↑ Blackledge, J M (March 10, 2010). Cryptography using Chaos (PDF) (Speech). Executive Speeches. Warsaw University of Technology.
- ↑ Maciej A. Czyzewski (2016). Chaos Machine: Different Approach to the Application and Significance of Numbers (Report). Cryptology ePrint Archive, Report 2016/468.
- ↑ Barker, Elaine; Barker, William; Burr, William; Polk, William; Smid, Miles (July 2012). "Recommendation for Key Management" (PDF). NIST Special Publication 800-57. NIST . Retrieved 19 August 2013.
- ↑ Kaneko, Kunihiko and Tsuda, Ichiro (2001). Complex systems : chaos and beyond a constructive approach with applications in life sciences. Physics and astronomy online library (in Japanese). Springer. ISBN 3-540-67202-8. Archived from the original on 2016-12-28. Retrieved 2016-12-27.
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