【摘要】 利用弱困难性假设构造强安全的加密系统在基于身份的加密(Identity-Based Encryption,IBE)中具有重要的理论与实际意义.本文基于弱困难性的判定性双线性Diffie-Hellman假设,构造了一个对于选择明文攻击安全的匿名的身份加密方案,解决了利用弱困难性假设构造强安全的基于身份加密系统的问题,同时也解决了基于身份的加密系统的隐私保护问题.与现有的基于较强困难性假设的方案相比,新方案实现的条件更容易满足,可以公开验证而且效率更高.更多还原

【Abstract】 Constructing a stronger security encryption system based on a w eaker computationally hard assumption is of great theoretical and practical importance in identity-based encryption. To solve this problem,w e,based on a w eaker assumption that the decisional bilinear Diffie-Hellman problem is hard,construct an anonymous identity-based encryption scheme w hich is secure against adaptively chosen ciphertext attack. This scheme can prevent an identity-based encryption system from disclosing privacy. Compared w ith the existing schemes based on stronger computationally hard assumption,the prerequisite of our scheme can be satisfied more easily,besides,it is publicly verifiable and more efficient.更多还原