A dynamic and verifiable multi-keyword ranked search scheme in the P2P networking environment

With the rapid development of the Internet, Peer to Peer(P2P) network has been applied in various fields. Users in P2P network also have a large amount of data, but users cannot provide enough storage space locally. More and more users choose to upload their own data to cloud server in order to save overhead and facilitate sharing their own data with other users. In order to ensure data security, researchers have proposed searchable encryption(SE) technology, and searchable encryption has been widely used. In this paper, a dynamic verifiable multi-keyword ranked search scheme is proposed under the background of P2P network and cloud storage service(CSS). On the basis of using secure kNN algorithm to encrypt index and traditional inner product algorithm to obtain ranked results, the scheme in this paper realizes forward and backward security by changing the structure of file vector and using modular residual computation. Meanwhile, the integrity and freshness of search results are verified by combining timestamp chain and Merkle tree. Finally, the security of this scheme under two threat models is analyzed, and the performance evaluation experiment is carried out on the document set.