SHA-1 (United States Government Secure Hash Algorithm, FIPS 180-1, ANSI

Definition: SHA-1 (United States Government Secure Hash Algorithm, FIPS 180-1, ANSI: 9.30-2, ISO/IEC 10118-3) SHA-1 is a popular hash algorithm. It converts an input file or message into a "unique" 160-bit fingerprint. This fingerprint is believed to be "unique"; while it is theoretically possible that two inputs could hash to the same fingerprint, it is nearly statistically impossible. Contrast: SHA-1 is currently (year 2001) considered to be the strongest hash function available. It has a larger size (160-bits vs. 128-bits) and has underground thorough scrutiny without discovery of weaknesses (such as MD5). On the other hand, it is one of the slower hash algorithms. History: SHA-1 is a slight variation of SHA. It adds a one-bit shift at one stage in order to overcome a theoretical weakness. SHA was based upon MD4, enhanced to overcome known weaknesses and increase the length to 160-bits. See also: integrity From Hacking-Lexicon

* Linux/Unix/Computing Glossary