A Secure Off-line Electronic Payment System Based on Bilinear Pairings and Signcryption

In this paper, we have designed an off-line e-cash payment system based on bilinear pairings for low-value transaction. We use the concept of proxy signcryption for communication among the entities. In our system, the token is issued & authenticated by Bank. Customer delegates the signing capability to Merchant. Bank verifies the original signer (customer) and proxy signer (Merchant) and ensures the originality of the transaction. Unlike the existing e-payment system question of double spending of e-cash arises because each transaction is made uniquely identifiable. Hence, no separate protocol is needed to check double spending. The proposed scheme provides anonymity, authenticity, confidentiality and fairness.