A Secure and Efficient Certificateless Short Signature Scheme

Abstract

Certificateless public key cryptography combines advantage of traditional public key cryptography and identity-based public key cryptography as it avoids usage of certificates and resolves the key escrow problem. In 2007, Huang et al. classified adversaries against certificateless signatures according to their attack power into normal, strong and super adversaries (ordered by their attack power). In this paper, we propose a new certificateless short signature scheme and prove that it is secure against both of the super type I and the super type II adversaries. Our new scheme not only achieves the strongest security level but also has the shortest signature length (one group element). Compared with the other short certificateless signature schemes which have a similar security level, our new scheme has less operation cost.

Keywords

• Cryptography
• Short signature
• Certificateless signature
• Bilinear parings