Analysis of Some Attacks on Awasthi and Lal's Proxy Blind Signature Scheme

A proxy blind signature combines the properties of proxy signature and blind signature. Recently, Awasthi and Lal proposed a more efficient proxy blind signature based on the proxy signature scheme proposed by Mambo et al.. Later, Sun et al. and Das et al. gave some attacks on Awasthi and Lal’s scheme respectively. In this paper, we analyze the two attacks and we point out that those attacks do not apply to Awasthi and Lal’s scheme.