A Fairness-Enhanced Micropayment Scheme

The micropayment scheme is widely used in the electronic payment, where the transaction value is tiny, meanwhile, the number of transactions is very huge. Recently, Liu and Yan proposed a lightweight micropayment scheme to achieve the efficiency, the fairness, and the privacy. However, the bank in the Liu–Yan’s scheme maybe obtain the illegal benefits by controlling the selective result. In this paper, an enhanced fairness micropayment scheme is presented to resist the attack from the malicious bank. In addition, considering that most of the users have no motivation to verify the result due to the tiny transaction value, the observers are employed to audit the process for ensuring the fairness.