Research Of Several Partial Blind Signature Schemes And Its Application To E-Cash

With the continuous improvement of the running speed of the computer, the security of the proposed partial blind signature scheme based on the problem which is computational complexity is increasingly threatened. As the important safeguard to security communication, as the important tool to authenticate the identities of communicate partners, partial blind signature is widely used in various fields of the construction of electronic information. In order to ensure the security of partial blind signature which is used in various, we wish to design more efficient and secure partial blind signature. There is important research significance and value in use.In this paper, we firstly introduce the concept of the partial blind signature, summarize and analyze the related properties and characteristics of partial blind signature. Based on this, we further analyze several partial blind signature schemes which have been proposed, master the ideas and skills of designing partial blind signature scheme. Based on the elliptic curve public key cryptography system, we propose new partial blind signature schemes, and we prove them security under the random oracle model. Besides, combined with the application background of electronic cash, we research and analyze the proposed electronic cash schemes, last, we apply the new partial blind signature scheme to the electronic cash system.In this paper, we design two new partial blind signature schemes, one is based on the identity public key cryptography system, the other is based on the public key cryptography system without trusted PKQ and both have their advantages and disadvantages. The scheme based on identity public key cryptography system, the signature verification is only need two bilinear mapping operations and an exponentiation operation on multiplicative group, it efficiently reduces the time complexity of the signature verification. The partial blind signature scheme without trusted PKQ because PKG only create part of the user secret key, it can not forge the legal signature of the user. At the same time, it solves the secret key custody problem. The unforgeability of the scheme is proved under adaptively chosen message and identity attack in the random oracle model. The research achievement is highly feasibility applied in electronic cash system.