Schneier 2004 (†825)Schneier, Bruce. "Cryptanalysis of MD5 and SHA: Time for a New Standard." (Computerworld, 19 August 2004).
- hash function (para 2-3): One-way hash functions are a cryptographic construct used in many applications. They are used with public-key algorithms for both encryption and digital signatures. They are used in integrity checking. They are used in authentication. They have all sorts of applications in a great many different protocols. Much more than encryption algorithms, one-way hash functions are the workhorses of modern cryptography. · In 1990, Ron Rivest invented the hash function MD4. In 1992, he improved on MD4 and developed another hash function: MD5. In 1993, the National Security Agency published a hash function very similar to MD5, called the Secure Hash Algorithm (SHA). Then in 1995, citing a newly discovered weakness that it refused to elaborate on, the NSA made a change to SHA. The new algorithm was called SHA-1. Today, the most popular hash function is SHA-1, with MD5 still being used in older applications. (†2158)