Abstract: In order to solve the problem of fair transaction in mobile payment, this paper proposes a mobile payment protocol without a trusted third part (TTP) based on a concurrent signature scheme, in which both the benefits of customers and merchants can be protected and the conspiracy problem can be avoided. The protocol possesses the characters of fairness and non-repudiation. At the same time, the scheme can avoid network congestion brought by a traditional TTP, and it can be applied to the trade of digital products in mobile environment.

Key words: mobile payment, concurrent signatures, fairness, non-repudiation

摘要： 为了解决移动支付的公平交易问题，本文提出了一种基于同时生效签名的无可信第三方的移动支付协议。本协议不仅能保证顾客在向商家付款的同时获得所购买的商品，还可以防止共谋问题的发生。该协议满足交易的公平性和不可否认性，并且避免了采用传统意义上的可信任第三方而引起的交易“瓶颈”问题，适用于移动环境下数字产品的交易。

关键词: 移动支付, 同时生效签名, 公平性, 不可否认性