混合可验证加密签名体制及应用

A Mixed Verifiably Encrypted Signature Scheme and It's Applications

在要求高效的密钥管理和中等的安全性的情况下,基于身份公钥密码已成为代替基于证书的公钥密码的一个很好的选择.本文在基于身份系统中,引入少数几个采用公钥证书实体充当裁决者,从而提出混合可验证加密签名的概念,并在Cheon基于身份签名体制的基础上,构造了一个有效的混合可验证加密签名体制;随后,本文讨论了混合可验证加密签名体制的安全模型,并在随机谕示模型下,基于双线性映射的计算性D iffie-Hellman问题难解性假设,证明本文体制是可证安全的.本文体制可用于构造基于身份的优化公平签名交换协议,这在电子商务等领域有着广泛的应用.

ID-based public key cryptography can be a good alternative for certificate-based public key setting,especially when efficient key management and moderate security are required. This paper proposes a primitive called mixed verifiably encrypted signature scheme （MVESS） and presents an efficient MVESS based on the D-based signature scheme due to Cheon,et. al. Then,we provide some theoretical discussions for the security model for MVESSs,and show that our new scheme can be proven to secure with the hardness assumption of the computational Diffie-Hellman problem of pairings in the random oracle model. Our new scheme can be used as blocks to build efficient D-based optimistic fair signature exchange protocols, which can be widely used in signing digital contracts, e-payment and other electronic commerce.