An identity-based dynamic group signature scheme for reputation evaluation systems

Abstract

As many Internet service platforms have launched reputation evaluation systems for applications, some malicious merchants are trying to disrupt the market competition environment by harassing evaluators or hiring netizens to give many untrue praises. Protecting evaluators’ identity privacy and the evaluation system’s fairness and justice is essential. Group signatures allow group members to sign messages anonymously in the name of a group. The group manager can find the actual signer in case of a dispute. Group signatures are widely used in reputation evaluation systems, digital cash, etc. However, most existing solutions are expensive, difficult to meet complex application requirements, and need more privacy protection or regulatory compliance. This paper proposes an identity-based dynamic group signature scheme for reputation evaluation systems standardized in IEEE P1363. We prove our scheme is secure in the random oracle model. Moreover, we provide a theoretical analysis of our scheme and conduct experiments by using the Miracl library on the PC platform to verify the analysis result. The analysis demonstrates that the size of the group public key and signatures do not increase with the number of group members. Our solution is efficient in reputation evaluation systems.