可证明安全的可变门限代理重签名方案

已有的大部分门限代理重签名方案的门限值是固定的，而可变门限代理重签名方案更符合实际应用的需求，即根据消息的重要性可灵活地选择不同的门限值进行门限重签名。在Ateniese G等人提出的代理重签名方案Sbi的基础上，利用中国剩余定理提出了一个具有短公开参数和签名长度的可变门限代理重签名方案，并给出了该方案的安全性证明。根据可变的门限值，每个代理者都能非交互地生成相应的重签名子密钥和验证公钥。与现有方案相比， 新方案占用通信带宽低、计算效率高。

A flexible threshold proxy re-signature scheme with provable security

The most existing threshold proxy re signature schemes have one threshold value. In many practical applications, the number of proxies is often dependent on the significance of the message to be re signed, which requires the threshold value to be changeable. Based on Ateniese G’s proxy re signature scheme Sbi and the Chinese remainder theorem, a flexible threshold proxy re signature scheme is proposed, and its security is proved. According to the changeable threshold value, each proxy can non interactively produce the re signature private key and the verification public key. Compared with other existing schemes, this scheme can provide better efficiency in terms of the communication and computation cost.