Abstract: In the random oracle model，Hash function is regarded as an ideal model of complete randomness which can’t be constructed actually.Utilizing bilinear paring of elliptic curves and threshold secret share，this paper proposes a fuzzy identity based signature scheme without the random oracle model based on Waters’s scheme.Compared with existing fuzzy identity based signature schemes，it doesn’t use Hash function to avoid the shortcoming of non-randomness of returned values，the system’s public parameters are less and the security can be reduced to the computation Diffie-Hellman assumption so that it can better meet the needs of practical applications.

Key words: fuzzy identity, signature, bilinear pairings, without random oracles

摘要： 在随机预言模型下，Hash函数被视为一个完全随机的理想模型，实际应用中却无法构造。利用椭圆曲线上的双线性对性质及门限秘密共享的思想，以Waters的签名方案为基础，设计了一种无随机预言模型的模糊身份签名方案。与已有的模糊签名方案相比，该方案的构造没有采用Hash函数，避免了Hash函数返回值无随机性的缺点;且系统公开参数少，安全性可规约到计算Diffie-Hellman（CDH）困难假定，从而能更好地满足实际应用需求。

关键词: 模糊身份, 签名, 双线性对, 无随机预言