An Offline and Transferable Multi-Bank Electronic Cash System Based on the Kylin Operating System

An efficient and forward-secure certificateless group signature scheme is proposed based on the idea of ACJT group signature scheme. Compared with ACJT, our signature length is shorter and the calculation amount is less, which improves the efficiency of our scheme. Based on the new group signature scheme and the convertible associated ring signature scheme, we design an offline and transferable multi-bank electronic cash system. The electronic cash system can manage multiple banks through the group signature system, and guarantee consumers’ unconditional anonymity through the ring signature system. Depending on a public ledger, our scheme can keep better track of electronic cash. The system not only inherits the security, anonymity, and efficiency from group signatures and ring signatures, but also satisfies more practical properties such as offline, unforgeability, anti-duplication, and transferability.