基于关键字的云加密数据隐私保护检索

Keyword-based Privacy-preserving Retrieval over Cloud Encrypted Data

云计算技术的蓬勃发展,使得越来越多的企业和个人将数据外包存储到云端并通过云服务提供对数据的管理。查询是用户访问云端数据获取信息的必不可少的操作。这样,保护用户查询隐私和云端数据隐私以及快速提供满足用户需求的查询结果成为了关键问题。私有信息检索可使查询用户和数据库持有者在双方私有信息互不泄露的情况下完成查询操作。针对现有私有信息检索方案在云环境、大容量数据中的局限性,提出一个基于同态密码体制以及MapReduce的计算安全信息检索协议并使用批量查询方法降低协议通信复杂度。将提出的协议作为构建块,利用完美哈希函数工具构建基于关键字的云加密数据检索方案,方案兼具隐私性、查询的高效率以及基于关键字的实用性。

More and more organizations and individuals outsource their data storage into cloud and using cloud-based services provide data management.Query providing user capabilities of accessing cloud data and obtaining information,is an important component of cloud services.Thus,how to protect both privacy of user queries and data privacy in cloud while providing query services and eventually providing query results meeting needs quickly and timely has become a vital concern.The private information retrieval(PIR)protocol allows user to perform a query from a database without revealing his private information;meanwhile the privacy of the database will be protected.Corresponding to limitations encountered in the applications of existing PIR protocol in the cloud environment and large capacity data scenario,a computational PIR protocol based on additively homomorphic encryption scheme and MapReduce was proposed.The protocol uses the batch queries method to lower the communication complexity.Further,we used proposed protocol as the building-block as well as perfect hash function tool to construct a cloud keyword-based encrypted data retrieval scheme.The scheme combines high query efficiency and the practicality of keyword-based retrieval.