An Off-line Electronic Cash System Based on Bilinear Pairings

E-cash enables the exchange of digital coins with value assured by the bank´s signature and with concealed user identity. Many electronic cash systems have been proposed with the proliferation of the Internet and the activation of electronic commerce. In this paper we propose a secure offline electronic cash system based on bilinear pairings. The security of the new system is under the computational Diffle-Hellman problem in the random oracle model.