Boolean symmetric searchable encryption

This article presents an original solution that we have designed to solve the problem of Boolean search over encrypted data in an outsourced server. In fact, this article aims to present the first scheme which can perform at the same time the three basic Boolean operations namely: conjunction, disjunction and negation. Indeed, Boolean symmetric searchable encryption BSSE is mainly based on the orthogonalization of the keyword field according to the Gram-Schmidt construction. Each document stored in the outsourced server is associated with a label which contains all the document keywords. On the other hand, we present a new search pattern for the BSSE scheme when the user sends a randomized query whenever he searches for a given boolean query. The randomized query hides the search pattern of the user since the search results were not associated to the deterministic queries. We formally define two security models for the label and the query security. In addition, the search complexity is in O(n) where n is the number of documents stored in the outsourced server.