Anonymous multi-vendor micropayment scheme based on bilinear maps

A hash-based micropayment scheme is introduced that takes advantage of good properties of bilinear maps, provides anonymity of the customers and makes it possible to shop at multiple vendors. The proposed scheme minimizes computational and financial costs. We proved that it possesses secure payment authorization under the chosen-target Computational Diffie-Hellman assumption in the random oracle model and customer´s anonymity and coin unreusability against any passive adversary with unlimited computational power.