Fair Divisible Off-line E-cash System Based on Elliptic Curves

In this paper, we proposed a fair divisible off- line electronic cash system based on elliptic curve discrete logarithm problem (ECDLP) and restrictive blind signature technique. The anonymity which the customer' s privacy depend on, can be revoked whenever needed so as to punish crime. By introducing trustee, fairness in the trade process prevents traders of both sides from loss. Trustee is only involved in during registration, disputation and revocation of anonymity. The divisibility can be achieved by using transferable cash, so the e- cash can be paid in precision. Analysis testifies its security and efficiency.