An Off-Line Divisible E-Cash Scheme Based on Smart Card

The unlinkable (N, K) payment is an important divisible solution, but the double-spending problem of the off-line schemes using this method will cause a great loss to the bank. In order to enhance the security of divisible e-cash systems, this paper presents an offline divisible e-cash scheme based on smart card using the elliptic curve cryptography, and describes the protocols in detail. The scheme solves double-spending effectively with two protective mechanisms: the prior restraint of smart card and the check of bank. Furthermore, security and efficiency of the scheme are analyzed.