The Message Authenticator Algorithm (MAA) was one of the first cryptographic functions for computing a message authentication code (MAC). It was designed in 1983 by

Donald Davies Donald Watts Davies, (7 June 1924 – 28 May 2000) was a Welsh computer scientist who was employed at the UK National Physical Laboratory (NPL). In 1965 he conceived of packet switching, which is today the dominant basis for data communic ...

and David Clayden at the

National Physical Laboratory (United Kingdom) The National Physical Laboratory (NPL) is the national measurement standards laboratory of the United Kingdom. It is one of the most extensive government laboratories in the UK and has a prestigious reputation for its role in setting and mainta ...

in response to a request of the UK Bankers Automated Clearing Services. The MAA was one of the first Message Authentication Code algorithms to gain widespread acceptance.

Development and standardization

The original specification of the MAA was given in a combination of natural language and tables, complemented by two implementations in C and BASIC programming languages. The MAA was adopted by

ISO ISO is the most common abbreviation for the International Organization for Standardization. ISO or Iso may also refer to: Business and finance * Iso (supermarket), a chain of Danish supermarkets incorporated into the SuperBest chain in 2007 * Iso ...

in 1987 and became part of international standards ISO 8730 and ISO 8731-2 intended to secure the authenticity and integrity of banking transactions.

Attacks

Later, cryptanalysis of MAA revealed various weaknesses, including feasible brute-force attacks, existence of collision clusters, and key-recovery techniques. For this reason, MAA was withdrawn from ISO standards in 2002 but continued to be used as a prominent case study for assessing various

formal methods In computer science, formal methods are mathematically rigorous techniques for the specification, development, and verification of software and hardware systems. The use of formal methods for software and hardware design is motivated by the exp ...

Formal specifications of the MAA

The MAA has been used as a prominent case study for assessing various

. In the early 1990s, the NPL developed three formal specifications of the MAA: one in Z, one in LOTOS, and one in VDM. The VDM specification became part of the 1992 revision of the International Standard 8731-2, and three implementations were manually derived from that latter specification: C, Miranda, and Modula-2. Other formal models of the MAA have been developed. In 2017, a complete formal specification of the MAA as a large

term rewriting system In mathematics, computer science, and logic, rewriting covers a wide range of methods of replacing subterms of a formula with other terms. Such methods may be achieved by rewriting systems (also known as rewrite systems, rewrite engines, or red ...

was published; From this specification
implementations of the MAA in fifteen different languages
have been generated automatically. In 2018, two new formal specifications of the MAA, in LOTOS and LNT, have been published.

References

External links

* * http://www.cix.co.uk/~klockstone/maa.htm * http://www.mars-workshop.org/repository/012-MAA.html {{Cryptography navbox, hash Cryptographic hash functions Broken hash functions Checksum algorithms