Non-commutative cryptography is the area of cryptology where the cryptographic primitives, methods and systems are based on algebraic structures like semigroups, groups and rings which are non-commutative.
One of the earliest applications of a non-commutative algebraic structure for cryptographic purposes was the use of braid groups to develop cryptographic protocols.
Later several other non-commutative structures like Thompson groups, polycyclic groups, Grigorchuk groups, and matrix groups have been identified as potential candidates for cryptographic applications.
In contrast to non-commutative cryptography, the currently widely used public-key cryptosystems like RSA cryptosystem, Diffie–Hellman key exchange and elliptic curve cryptography are based on number theory and hence depend on commutative algebraic structures.
Selected Areas in Cryptography (SAC) is an international cryptography conference held every August in Canada since 1994.
The first workshop was organized by Carlisle Adams, Henk Meijer, Stafford Tavares and Paul van Oorschot.
Through 1999, SAC was hosted at either Queen's University or Carleton University, but starting in 2000, locations have ranged across Canada.
SAC has featured research presentations on many cryptographic topics, with a traditional focus on the design and analysis of block ciphers.
SAC is regarded as a high-quality venue for presenting cryptographic results, and is the only cryptography conference held annually in Canada.
Since 2003, SAC has included an invited lecture called the Stafford Tavares Lecture, in honor of one of its original organizers and strongest supporters.
