Entity authentication schemes using braid word reduction

Artin’s braid groups currently provide a promising background for cryptographical applications, since the first cryptosystems using braids were introduced in [2, 3, 18] (see also [22]). A variety of key agreement protocols based on braids have been described, but few authentication or signature schemes have been proposed so far. We introduce three authentication schemes based on braids, two of them being zero-knowledge interactive proofs of knowledge. Then we discuss their possible implementations, involving normal forms or an alternative braid algorithm, called handle reduction, which can achieve good efficiency under specific requirements.