云存储中加密数据的相似检索技术应用研究

随着云存储的广泛应用，大量数据存储在云服务器。尽管云服务提供很多便利，但数据的隐私及安全性一直是重点关注的问题，为解决数据安全问题需要将外储数据以加密的形式进行存储。加密存储的方式保护了数据不被恶意访问，然而数据的一些重要的基本应用如检索等不能实现。为了在不泄露隐私的条件下实现对加密数据的检索，很多可检索的加密方案被提出。然而，这些方案多数只能处理确切的关键字匹配检索而不能进行相似的关键字检索，相似检索在现实应用中又极其重要。本文提出一个高效的支持加密数据相似检索的方案，为了实现相似密文的检索我们利用一种被称为位置敏感的哈希算法。为了确保数据的机密性和安全性，我们给出了严格的安全定义，并且在安全定义下证明了方案的安全性。 

Research on Similar Keyword Search over Encrypted Data in Cloud

As Cloud Computing becomes prevalent, more and more sensitive information is centralized into the cloud. Although cloud based services offer many advantages, privacy and security of the sensitive data is a big concern. For the protection of data privacy, sensitive data usually -has to be encrypted before outsourcing, which makes effective data utilization as retrieval a very challenging task. Some solutions were proposed to securely search over encrypted data through keywords, however these techniques support only exact keyword search. That is, there is no tolerance of minor typos and format inconsistencies which, on the other hand, are typical user searching behavior and happen very frequently. In this paper, effective fuzzy keyword search over encrypted cloud data is proposed while maintaining keyword privacy. In our solution, we exploit locality sensitive hashing to quantify keywords similarity. Through rigorous security analysis, we show that our proposed solution is secure and privacy-preserving.