A Security Enforcement ID-Based Partially Blind Signature Scheme

Partially blind signature, which allows a signer to sign a partially blind message including pre-agreed information, is a variant of blind signature. In 2007 Hu et al presented an efficient ID-based partially blind signature scheme that was believed as a secure one. In 2008, Tseng et al shows that Hu et al´s scheme could suffer from serious forgery attack, but they didn´t propose the corresponding improved scheme. In this paper we efficiently improve Hu et al´s partially blind signature scheme and at the same make the improved one more secure to prevent against the forgery attack proposed by Tseng et al. Our proposed improvement meets the security property of partially blind signature such as the unforgeability, partially blind, verifiability and non-deniability.