SDKSE:A Secure Dynamic Keyword Searchable Encryption Scheme for Email Systems

Abstract

Cloud computing has an significant impact on both academia and industry with its rapid development. by moving expensive operations like search to cloud, we are able to carry out complicated tasks efficiently. At the same time, cloud security has become a major concern. Malicious clouds are likely to sell privacy information for extra benefit. In order to protect privacy, data are encrypted before being uploaded to cloud. So how to handle encrypted data becomes a new challenge. In this paper we propose SDKSE: a secure dynamic keyword searchable encryption scheme for email systems under cloud computing environment. It is able to update files and keywords at any time. The indexes and the trapdoors generated in the scheme are constant size. In addition, we prove that it is adaptively Trapdoor-IND-CKA and Index-IND-CKA in the standard model.