With the recent advancement of cloud storage services, many cloud customers (data owners) are migrating their data from local storage to cloud data storage to reduce maintenance cost. Once data is outsourced, the data owners loose control over their data, evolving various security and privacy issues. To resolve this issue, data encryption is an effective solution. Meanwhile, to increase the utilization of the encrypted outsourced data, searchable encryption would be an efficient tool capable enough to search over encrypted data. In this work, we propose a novel public-key based searchable encryption scheme (SEPS) using an inverted index data structure. We show that SEPS achieves better performance than previous efforts (both theoretically and experimentally). We prove the security of the proposed scheme using Bilinear Diffie–Hellman assumption. SEPS withstands keyword guessing attack and achieves trapdoor privacy. On the top, the index generation process of the proposed scheme is secure against chosen keyword attack. AVISPA tool is also used for the formal security verification of SEPS and found to be attack resistant.

随着最近云存储服务的进步，许多云客户（数据所有者）正在将他们的数据从本地存储迁移到云数据存储，以降低维护成本。一旦数据外包，数据所有者就会失去对其数据的控制，从而引发各种安全和隐私问题。为了解决这个问题，数据加密是一个有效的解决方案。同时，为了提高加密外包数据的利用率，可搜索加密将是一种足以搜索加密数据的有效工具。在这项工作中，我们提出了一种使用倒排索引数据结构的新型基于公钥的可搜索加密方案（SEPS）。我们表明 SEPS 比以前的工作（在理论上和实验上）取得了更好的性能。我们使用双线性 Diffie-Hellman 假设证明了所提出方案的安全性。SEPS 抵御关键字猜测攻击，实现陷门隐私。最重要的是，所提出方案的索引生成过程对于选择关键字攻击是安全的。AVISPA 工具还用于 SEPS 的形式安全验证，并发现具有抗攻击性。