关键词: 隐私保护, 匿名订购, 可充值的电子钱包, sigma协议, 黑盒零知识, 有条件的匿名性, 标准模型

Abstract: There has been no efficient anonymous subscription system which supports customers to purchase some service for a number of times decided by themselves. Previous systems fail to balance both the resistance of misusing anonymity and the protection of customers’ privacy. Moreover, systems in the literature are all built on standard sigma-protocols, which implies that those systems can only preserve the weak property of HVZK（Honest Verifier Zero-Knowledge） in the random oracle model. To combat the above difficulties, a revised system is proposed, which is constructed by applying the recent rechargeable electronic wallet to the Au-Susilo-Yiu non-interactive k-times anonymous authentication. The underlying sigma-protocols are strengthened to black-box zero-knowledge arguments by borrowing the technique of Zhao et al. The proposed system fulfills several properties simultaneously, i.e., unlimited subscription, service type, non-transferable subscription and reusable tokens. In particular, it is proved secure in the standard model.

Key words: privacy protection, anonymous subscription, rechargeable electronic wallet, sigma-protocols, black-box zero-knowledge, conditional anonymity, standard model