关键词: 基于身份密码学, 多代理签名, 离散对数问题, 随机预言模型

Abstract: The identity-based multi-proxy signature schemes employing computation-intensive bilinear pairing operations have higher cost of computing. Based on the elliptic curve group, a pairing-free identity-based multi-proxy signature scheme is proposed. In the new scheme, user’s private key generation algorithm, delegation generation algorithm and multi-proxy signature generation algorithm are all derived from Schnorr’s short signature scheme. In the random oracle model, the new scheme achieves provable security, and its unforgeability is deduced to a polynomial time adversary solving the discrete logarithm problem. Comparative analysis shows that the new scheme is more efficient in computation.

Key words: identity-based cryptography, multi-proxy signature, discrete logarithm problem, random oracle model