An ID-based proxy signature scheme secure against proxy key exposure

Proxy Signature is very important technologies in secure e-commerce. In this paper, we study the security of three ID-based Proxy Signature Scheme Against Proxy Key Exposure. We point out that those schemes are vulnerable to proxy key exposure attack. Then we propose a new scheme to overcome this defect and analyze its security and efficiency. We claim that our new scheme is more efficiency and can be proved secure against proxy key exposure in the random oracle model. In particular, our scheme doesn't need secure information channel.