Privacy concerns in outsourced cloud databases have become more and moreimportant recently and many efficient and scalable query processing methodsover encrypted data have been proposed. However, there is very limited work onhow to securely process top-k ranking queries over encrypted databases in thecloud. In this paper, we focus exactly on this problem: secure and efficientprocessing of top-k queries over outsourced databases. In particular, wepropose the first efficient and provable secure top-k query processingconstruction that achieves adaptively CQA security. We develop an encrypteddata structure called EHL and describe several secure sub-protocols under oursecurity model to answer top-k queries. Furthermore, we optimize our queryalgorithms for both space and time efficiency. Finally, in the experiments, weempirically analyze our protocol using real world datasets and demonstrate thatour construction is efficient and practical.
展开▼
