Secure Range Query Processing over Untrustworthy Cloud Services

Database-as-a-service is a relatively new cloud computing service offered on a pay-per-use basis and providing on-demand access to a database. The way data has dramatically increased in volume explains its success, while security and privacy issues arise, leaving enterprises, in particular, exposed to the risk of leakage of the data which they entrust to specialized cloud service providers or to other parties in order to reduce storage and query processing costs. Since traditional encryption does not support the execution of queries on encrypted data, this paper focuses on the problem of secure computation on encrypted data and puts forward a cloud database model that supports secure range query processing and retrieval of multi-dimensional (i.e. multi-attribute) data. It proposes two schemes to resist practical attacks operating on the basis of powerful background knowledge. A performance and efficiency evaluation of these schemes is also carried out to confirm their efficiency and practicability.