Research For Anonymous Group Identification Protocol And Identification Scheme Against Reset Attack

First, two provably secure group identification schemes are presented in this dissertation.1) We extend De Santis, Crescenzo and Persiano's (SCP) anonymous group identification scheme to the discrete logarithm based case. With the help of this basic scheme, we provide a 3-move anonymous group identification scheme, which is more efficient than that presented in [SCPM, CDS]. 2) We also extend the original De Santis, Crescenzo and Persiano's anonymous group identification scheme to the general case where each user holds public key which is chosen by herself independently. The communication cost for one round execution of the protocol is 2mk, where k is bit length of public key n and m is the number of users in the group.2) Second, we develop an efficient identification scheme based on (the basic and a variation of) Cramer-Shoup's test function. The scheme is provably secure against attack under post-processing model provided the hardness assumption of the decisional Dffie-Hellm an problem as well as the existence of collision free hash functions .