Research On E-Cash Protocol Based On Multi-Level Proxy Blind Signature And Each Node Can Be Paid

With the rapid development of electronic commerce, the secure and efficient electronic payment technologies become one of the most important problems to be resolved in information society. Aiming at the problems of the inferior bank in reality how to delegate its superior bank to issue e-cash and the drawbacks of the existed divisible e-cash protocols, this paper makes an investigation on how to use the multi-level proxy blind signature technologies to design an off-line e-cash protocol that can efficiently delegate its superior bank to issue e-cash in multi-level organizational structure and how to use the idea that each node can be paid to design an efficiently divisible e-cash protocol, thus it provides theoretic and technological support for the practical application of the e-cash system and meets the evolving needs of the application of the Internet Age.Firstly, in order to enable each bank of multi-level organization structure can delegate its superior bank to issue e-cash, this paper proposes an off-line e-cash protocol without trusted third party, which based on elliptic curve cryptography. Through the combination of multi-level proxy blind signature and smart card, it solves the problem of delegating issue e-cash in multi-level situation and the problem of double-spending detection in e-cash. The basic description of the protocol and the detail design of the protocol is presented, they are the set up of the system parameters, the proxy protocol, the opening account protocol, the withdrawal protocol, the spending protocol, the deposit protocol and the tracing protocol. Furthermore, the security properties of the protocol satisfied are fully analyzed.Secondly, aiming at the drawbacks of the existed divisible e-cash schemes based on binary tree just can spend root node's corresponding denomination after one execution of the withdraw protocol, this paper proposes a divisible e-cash protocol without trusted third party, which based on the idea of each node can be paid and zero knowledge proof. After the basic description of the protocol, each part of the protocol is fully designed. Furthermore, the anonymity, unforgeability, unlinkability, exculpability, revocable anonymity, divisibility and the efficiency of the protocol are analyzed.