Some Proxy Signature and Designated Verifier Signature Schemes Over Braid Groups

Braid groups have recently attracted the attention of many cryptographers. These highly non-commutative groups are useful to construct cryptosystems. They provide numerous mathematical hard problems such as the conjugacy search problem, braid decomposition problem and root problem. Moreover, the group operation and generation of the parameters can be implemented quite efficiently. Braid groups were introduced in 1947 by Artin and were first used to construct a Diffie-Hellmann type key agreement protocol and a public key encryption scheme by Ko et al.