| In recent years,the rapid development of the network economy has spawned many new businesses and changed people’s lives and payment methods,and electronic payment is gradually becoming the mainstream payment channel.E-cash has strong competitiveness in various payment means with its privacy,convenience,efficiency and security.In this thesis,a double blind compact e-cash scheme based on bilinear map is constructed and the following work is mainly carried out:(1)This thesis studies and analyzes compact e-cash schemes,and finds that existing compact e-cash schemes do not take into account the privacy needs of the payee in the transaction process and the privacy protection needs of the subsequent e-cash payment.Combined with the transferable e-cash scheme,this thesis constructs a double-blind compact e-cash scheme.During the transaction,the payer and the payee cannot determine each other’s identity and the payee can anonymously transfer the received e-cash into the subsequent expendable coin.In order to solve the problem of validity authentication of both parties in the case of double-blind,the scheme combines bilinear map and CL signature technology to construct an electronic wallet and authentication certificate to replace the user’s public key for validity authentication of the collection and payment.In order to realize the anonymous transfer of the electronic coin received by the payee,the scheme adds an electronic coin transfer protocol.The payee can apply to the bank for transfer of the electronic coin received into the subsequent expendable coin by virtue of its authentication certificate.The double-blind compact e-cash scheme constructed in this thesis meets the requirements of balance,anonymity of users,traceability of dual payers and exculpability.This thesis analyzes the storage space efficiency,computing efficiency and function of the constructed double-blind compact e-cash scheme.Compared with other e-cash schemes of the same type,this scheme ensures the privacy requirements of the payee in the transaction process and the subsequent e-cash payment privacy requirements,and is more practical.(2)In this thesis,an electronic cash system is designed to implement each interaction protocol in the double-blind compact electronic cash scheme.There are two types of entities in the system:users and banks.The user selects as the payee or payer according to the actual scenario.The payee application function includes applying for authentication certificate,sending anonymous certificate,receiving electronic coin,applying for transferring and depositing electronic coin.The payer application function includes applying for electronic wallet,receiving anonymous certificate and generating electronic coin.The bank-side application function includes generating public parameters,issuing electronic wallets,issuing authentication certificates,depositing and transferring electronic coin,and tracking dual payers.By using the Android development framework and the SpringBoot development framework,this thesis realizes all functions of the user application and the bank application.This thesis measures the running time of the core algorithm of each interaction protocol in the electronic cash system,and analyzes the time consumption distribution. |
