An Efficient Electronic Cash Scheme with Multiple Banks Using Group Signature

In 2008, an electronic cash scheme with multiple banks based on group signatures was proposed by Wang et al. They adopted a group blind signature scheme based on bilinear pairings to generate the electronic cash and it can be verified by the bilinear pairings operation. However, we find some security problems in their approach. By the way, the cost of communication and computation in their scheme can be improved further. Hence, we propose an efficient and secure e-cash scheme from bilinear pairings with multiple banks. Not only can our approach solve all the security problems in Wang et al.’s scheme but also offer lower computation and communication cost.