Offline E-cash System with Finite Circulation Period Based on Elliptic Curve

Abstract

To prevent e-cash from double-spending and unlimited increase in the records of databases,an improved offline e-cash system based on elliptic curve cryptography was proposed.The improved system utilizes good properties of elliptic curve cryptography system and adopts zero knowledge proof.Partial blind signature based on elliptic curve cryptography ensures that the e-cash is valid only in the period issued by the bank according to the withdrawal protocol,and the historical record of the e-cash that exceeds the valid period will be removed,which greatly reduce the amount of traffic and effort of calculation and improve the efficiency.The security of the system was improved by adopting the elliptic curve zero knowledge proof in the payment protocol.