基于身份的环签密方案

Identity-based ring signcryption scheme

目的研究如何设计安全、高效的基于身份的环签密方案。方法首先提出了一个高效的基于身份的签名方案,给出了其安全性证明。其次,基于该签名方案,构造了一个基于身份的环签密方案。结果该环签密方案能够使消息发送者以完全匿名的方式发送消息,且可以同时实现保密性和认证性两种功能,在计算双线性Diffie-Hellman假设下证明了该方案可以抵抗适应性选择密文攻击。结论与已有的基于身份的环签密相比,本文方案效率更高,且消息的扩张长度大大降低,非常适用于传输带宽受限的环境。

Aim To study how to design a secure and efficient identity-based ring signcryption. Methods An efficient and provably-secure identity-based signature （IBS） scheme is proposed in this paper, and then a new identity-based ring signcryption scheme （IBRSC） based on our IBS scheme is presented. Results Using this IBRSC scheme, a sender can anonymously send a message, and the confidentiality and authenticity of the message are realized at the same time. It＇s proved that our IBRSC scheme is secure against adaptively chosen ciphertext attack under the computational bilinear Diffie-Hellman assumption. Conclusion Compared with the existing IBRSC schemes, our scheme achieves higher efficiency and has very short information expansion, which can be used in environments with stringent bandwidth constraints.