Efficient offline micropayment protocol for multi-vendor

With the rapid development of e-commerce, online services have become a usual part of our lives, such as online gaming, music or software downloads, pay-per-view content, and membership fees. But the amount of money spent for these services often is only a few multiple of the smallest currency unit. These kinds of payments are called micropayment. Therefore, in the field of electronic payment, micropayment is one of the most popular researches. The earliest and still most popular micropayment scheme is PayWord. But in the meanwhile, some problems still exist in the PayWord protocol, such as security, fairness, anonymity, and customer credibility. Moreover, PayWord is designed for a single vendor and is not efficient for multi-vendor purchasing. In this paper, an efficient offline micropayment scheme for multi-vendor is proposed. Compared with other micropayment schemes, our scheme not only improves its efficiency since no public key operations are needed, but also provides security, fairness, anonymity, and multi-vendor support.