Hash (cryptography)

In cryptography a hash or message digest is a fixed-size digest which can be calculated from an input text of any size up to some large limit. While cryptographic principles are used, these functions are used in manners quite different than two-way, or even one-way full-text cryptographically protected communications. The primary applications of hashes and message digests are as means of error detection, source authentication, or data integrity protection.

MD4 and descendants

MD4

Message Digest algorithm number 4 was from Ron Rivest. It is no longer used, replaced by its descendants. A specification is in RFC 1320.

MD5

RFC 1321 gives a specification and RFC 1820 a performance analysis.

RIPE-MD

This was a European standard.

The Advanced Hash Standard

In 2005, the US National Institute of Standards and Technology (NIST) began the process of defining a new hash standard, SHA-3 or the Advanced Hash Standard or just AHS. There is a NIST page with details and links.

The overall process and methodology are similar to what they did for the AES contest, choosing a new cipher standard which became the Advanced Encryption Standard. Starting in 2005, they sponsored two public workshops contest to discuss the state of the hashing art, then issued a draft requirements document and invited public comment. After revising the requirements, they issued a call for submissions in November 2007. The deadline on that was October 31, 2008.

As of early November, the deadline has passed and NIST have received 64 entries. They are going through them to see which ones actually meet all submission criteria. Once that is done, those "complete and proper" submissions will become the first round candidates and all their design documents will be public on the NIST site. Meanwhile, there are at least two other sites with partial lists and links to design documents, the SHA-3 Lounge and the SHA-3 Zoo.

There will be more conferences, then a narrowing of the field to a group of finalists, more analysis and another conference, then a final selection. Target date for completion of the process and release of the new standard is 2012.

Skein

From Bruce Schneier and others: [1]

MD6

From a team led by Ron Rivest.

CubeHash

From Dan Bernstein, [2]

Essence

From Jason Worth Martin [3]

Sgàil

Peter Maxwell [4]

EnRUPT

Sean O'Neil [5]

NaSha

Smile Markovski and Aleksandra Mileva [6]

Maraca

Robert Jenkins [7]