A new postpaid micropayment scheme is first proposed to protect customers' anonymity and provides customers' convenience. Due to customers' anonymity, customers can anonymously transact with merchants and obtain the goods/services before being charged. This scheme satisfies three properties of anonymity. First, the customer's identity is protected by a pseudonym. Second, the adversary cannot figure anonymous customers out by tracing their payments. Third, there is a trusted authority to revoke customers' anonymity when some disputes happen. On the other hand, the postpaid function provides customers with the convenience of using the credit to buy goods/services.
淡江理工學刊=Tamkang Journal of Science and Engineering 11(3)，頁253-264