Research On Electronic Cash Security System

With the rapid development of the information era, a high degree ofinteroperability in e-commerce transactions has become an important factor inpromoting the rapid development of financial. In recent years, as a newelectronic payment theory, electronic cash has been extensively studied,electronic cash has the characteristics of traditional currency trading, electroniccash is flexible, efficient and anonymous, and it can not be tracked for closelylinking with the open Internet platform. With globalization of electroniccommerce, how to ensure confidential personal information on the Internet, howto authenticate user and shop status in transaction, and how to ensure theinformation security of both user and shop in the transaction process, such asnon-repudiation, anti-replay, these are the basis of ensuring normal electronictransactions and the key factors to promote electronic commerce in furtherdeveloping.Considering from the perspective of specific e-commerce security,information security theory and cryptography technology related to electronicpayment and electronic cash systems are analyzed in detail, for instance, digitalsignature verification algorithm, blind signature algorithm and hash function.Elliptic curve digital signature algorithm and hyperelliptic curve digital signaturealgorithm are improved and the algorithm instances are implemented. In theimproved algorithm scheme, the thought of “translation transform” points areillustrated in detail, and “translation transform” points are adapted in themapping relationship between public key point and private key parameter overelliptic curve and division and division matrix over hyperelliptic curve, and safety performance of the improved algorithm are evaluated. The improvedalgorithm is applied to the detailed design of electronic cash security system.Brands electronic cash scheme are introduced and analyzed, including Schnorralgorithm adapted in Brands scheme and dealing protocol process in the scheme.A secure electronic cash system scheme based on Brands scheme is proposed inthe thesis. Initialization process of electronic cash parameters, protocol ofdepositing and withdrawing electronic cash, transportation dealing protocol ofelectronic cash between users and shop, and arbitration agreement protocolexecuted by trusted third party under the condition of controversy are allimproved in the proposed scheme. Revocable anonymity, offline, divisibility andfairness of electronic cash are realized in the shceme. Analysis of the improvedscheme shows the safety of the improved scheme integrated with encryptiondecryption algorithms and digital signature algorithm and the high efficiency ofthe scheme.On the basis of research of the protocol on electronic scheme, the electronicpayment system protocol implementation process based on the improveddelectronic cash shceme is described in detail, an electronic cash security systemrelied on object oriented programming thinking is designed, including analysis ofelectronic payment requirement in detail, use case description, functional needsmodule design in shopping on Internet and design and analysis of electronic cashdatabase.Finally, comprehensive assessments of the safety and efficiency of theelectronic cash system are made, it shows that e-cash theory reached the level ofinformation security and cryptography security requirements. From theperspective of the divisibility, transportation and cryptography algorithm of theelectronic cash, future research direction and development of electronic cashsystem are made and envisaged in the thesis.