Fuzzy Keyword Search over Encrypted Cloud Data with Dynamic Fine-grained Access Control

Due to the increasing popularity of cloud computing and privacy preservation concerns, sensitive data should be encrypted before outsourcing to the cloud and data utilization becomes a challenging issue. Searchable encryption (SE) is a promising technique to address this problem. Most existing searchable encryption schemes only support accurate keyword but fuzzy keyword search schemes are appreciated in practice. Moreover, in some application scenarios like the video on demand systems, data owners only hope to give the access of their data to those who have payed but authenticated user identity may often change. Therefore, dynamic user attribute updating should be considered. To solve about issues, we propose a fuzzy secure keyword search scheme over encrypted cloud data with dynamic fine-grained access control. We design a novel fuzzy keyword index to retrieve corresponding documents. To reduce the computation cost, the cloud server selects most relevant top-k documents and return them to the data users. The ciphertext-policy attribute based encryption (CP-ABE) technique is introduced to implement fine-grained access control. Meanwhile, the basic CP-ABE is improved to meet the practical need of user attribute updating. Extensive security and performance analysis demonstrates that our proposed scheme is highly efficient and can satisfy the security requirements for fuzzy keyword search over encrypted cloud data.