Discuss the problem of infinite increasing coin list in anonymous E-cash systems, which reduce the efficiency of whole system greatly. Though some methods are suggested, no one can solve the problem with high efficien...Discuss the problem of infinite increasing coin list in anonymous E-cash systems, which reduce the efficiency of whole system greatly. Though some methods are suggested, no one can solve the problem with high efficiency and flexibility. Here, we use the technique of adding information in blind signatures to deal with this problem. Through adding timestamp in signatures, we can separate the valid period of all used coins into pieces. Only the coins in the last stage are recorded. So the scale of the coins list is controlled. We also analyze the anonymity of these data, and add some indispensable restrictions to them. These restrictions can ensure that the imported data don’t break the anonymity of the customers. In order to fulfill these qualifications, we lead to the concept of restricted common data (RCD). Furthermore, we propose two schemes to add RCD in the blind signature. The simple one is easy to implement, while the complex one can note the value of the coin. The usage of RCD leads to little additional cost, as well as maintaining the anonymity of customers. This method fits for most kinds of anonymous E-cash systems.展开更多
In this paper, an efficient fair e-cash system is presented. Based on the improved Brands’ e-cash scheme, it is expanded by adding two roles, government and judges. The user can keep unconditionally anonymous in norm...In this paper, an efficient fair e-cash system is presented. Based on the improved Brands’ e-cash scheme, it is expanded by adding two roles, government and judges. The user can keep unconditionally anonymous in normal transactions. Authorized by the judges, the government can remove the identity of an illegal user with the help of the bank. So such misuse as blackmailing or money laundering can be prevented. Therefore, this scheme is more efficient, more suitable for adopting pre-processing and post-processing and more practical. In the paper, the details of the scheme are described, its security is proved, and its efficiency is analyzed.展开更多
Electronic check systems, as one of electronic payment systems, are more desirable than other electronic cash systems. In the system, only a single cheek is used to pay any price that is not more than the face value. ...Electronic check systems, as one of electronic payment systems, are more desirable than other electronic cash systems. In the system, only a single cheek is used to pay any price that is not more than the face value. The main problem in check systems is to design an efficient refund mechanism that makes refired cheeks undistinguished from initial checks during payment and deposit. The problem of anonymity control also called fairmess is also an important issue in check systelns. All check systems yet are unconditional anonymity that opens the door to misuse for crime such as laundering and blackmailing. In this paper, the notion of anonylnity revocation is introduced to electronic check system for the fitst thne, and a model of fair electronic check system is proposed. An effieient fair online electronic check system with reusable refund is presented. In the system, a passive trustee is elnployed to revoke the anonymity of unhonest users. Moreover, the system solves the reusability problem of refunds thanks to the RSA-based partially signature. The system is efficient and meets all basic security requirements.展开更多
In the composition, we got A country gover nment. The A country infant industry and the B country industry three join body’ s facties set and pay off function, use thinking of opposite induction took out subjame per...In the composition, we got A country gover nment. The A country infant industry and the B country industry three join body’ s facties set and pay off function, use thinking of opposite induction took out subjame perfect equlibium’s answer way and steps.展开更多
文摘Discuss the problem of infinite increasing coin list in anonymous E-cash systems, which reduce the efficiency of whole system greatly. Though some methods are suggested, no one can solve the problem with high efficiency and flexibility. Here, we use the technique of adding information in blind signatures to deal with this problem. Through adding timestamp in signatures, we can separate the valid period of all used coins into pieces. Only the coins in the last stage are recorded. So the scale of the coins list is controlled. We also analyze the anonymity of these data, and add some indispensable restrictions to them. These restrictions can ensure that the imported data don’t break the anonymity of the customers. In order to fulfill these qualifications, we lead to the concept of restricted common data (RCD). Furthermore, we propose two schemes to add RCD in the blind signature. The simple one is easy to implement, while the complex one can note the value of the coin. The usage of RCD leads to little additional cost, as well as maintaining the anonymity of customers. This method fits for most kinds of anonymous E-cash systems.
文摘In this paper, an efficient fair e-cash system is presented. Based on the improved Brands’ e-cash scheme, it is expanded by adding two roles, government and judges. The user can keep unconditionally anonymous in normal transactions. Authorized by the judges, the government can remove the identity of an illegal user with the help of the bank. So such misuse as blackmailing or money laundering can be prevented. Therefore, this scheme is more efficient, more suitable for adopting pre-processing and post-processing and more practical. In the paper, the details of the scheme are described, its security is proved, and its efficiency is analyzed.
基金国家高技术研究发展计划(863计划)，the National Natural Science Foundation of China
文摘Electronic check systems, as one of electronic payment systems, are more desirable than other electronic cash systems. In the system, only a single cheek is used to pay any price that is not more than the face value. The main problem in check systems is to design an efficient refund mechanism that makes refired cheeks undistinguished from initial checks during payment and deposit. The problem of anonymity control also called fairmess is also an important issue in check systelns. All check systems yet are unconditional anonymity that opens the door to misuse for crime such as laundering and blackmailing. In this paper, the notion of anonylnity revocation is introduced to electronic check system for the fitst thne, and a model of fair electronic check system is proposed. An effieient fair online electronic check system with reusable refund is presented. In the system, a passive trustee is elnployed to revoke the anonymity of unhonest users. Moreover, the system solves the reusability problem of refunds thanks to the RSA-based partially signature. The system is efficient and meets all basic security requirements.
文摘In the composition, we got A country gover nment. The A country infant industry and the B country industry three join body’ s facties set and pay off function, use thinking of opposite induction took out subjame perfect equlibium’s answer way and steps.
