Efficient proxy signature schemes using self-certified public keys

摘要

Elaborating on the merits of self-certified public key systems and message recovery signature schemes, this paper proposed a proxy signature scheme based on discrete logarithms and its variant based on elliptic curve discrete logarithms. The proposed schemes are efficient in the terms of communication overheads and computational efforts due to the following reasons: (i) The signing message is unnecessary to transmit, since the verifier can recover it from the proxy signature. (ii) The tasks of verifying the authenticity of public keys, validating the proxy signature, and recovering the signed message are carried out simultaneously in a single step. (iii) No certificate is required for validating the public key. As compared with the previous works, which were implemented with the certificate-based public key system, the proposed schemes are more secure and efficient. In addition, the elliptic curve variant is especially suitable for the cryptographic applications with limited computing power and storage space, since its lower computation efforts and shorter key lengths.