Description

Abstract

In this paper, we propose a family of techniques that allow processing of NN queries in an untrusted outsourced environment, while at the same time protecting both the POI and querying users’ positions.  The first approach is to use cloaking regions (CRs). Users send their current location as the query parameter, and wish to receive as result nearest-neighbors (NNs).  But typical data owners do not have the technical means to support processing queries on a large scale, so they outsource data storage and querying to a cloud service provider.

Many such cloud providers exist who offer powerful storage and computational infrastructures at low cost. However, cloud providers are not fully trusted, and typically behave in an honest-but-curious fashion. Specifically, they follow the protocol to answer queries correctly, but they also collect the locations of the POIs and the subscribers for other purposes.We present an extensive performance evaluation of our techniques to illustrate their viability in practice.