In this paper,the running modes of the two-party cryptographic protocols are used to analyze the two authentication and key agreenment protocols,and attack on the protocols is discovered. Finally,two improved protocols are given.
An ([n/3]-1)-resilient Asynchronous Byzantine Agreement Protocol (ABAP) that combines verifiable signature sharing and random secret sharing is proposed. The protocol works in the asynchronous network environment and produces Byzantine agreement within a fixed expected number of computational rounds. The correctness of the protocol is proved in theory.
