面向云的密文检索隐私保护研究

With the development of cloud storage services, more and more users choose to store their information and data in the cloud and use Cloud Service Provider to manage their data. In order to ensure the security of the data in the cloud, users will encrypt their data before store it in the cloud. Although the encryption ensure the security of the data, it brings some problem to users when searching their data at the same time. At present, the research on the technology of the plain text has been relatively mature, how to study for a retrieval technology over ciphertext in the cloud is the key to ciphertext retrieval technology. In this paper, we analyze the existing search algorithm over ciphertext, for the problem that most algorithm will disclosure user's access patterns, we propose a new method of private information retrieval supporting keyword search which combined with homomorphic encryption and private information retrieval. This method can achieve the query operation without disclose private information of both sides. In view of the efficiency problem of the private information retrieval scheme, we introduce the MapReduce into the search algorithm which can meet both the efficiency and privacy requirements.