Research On Location Privacy-preserving Nearest Neighbor Query Based PIR

The rapid development of positioning and mobile communication promotes the popularity of location-based services.Nearest neighbor querying witness its prosperity in location-based services.With the increasing attention people pay to individual privacy,location privacy preserving k nearest neighbor querying becomes a hot topic.In recent years,private information retrieval techniques attract increasing concerning from researchers for its merits in providing high location protection strength,as well as its independence on any trusted third-party.A series of methods are proposed based on PIR to surmount the problem of location privacy protection in nearest neighbors querying.This paper proposes two new method based on this technique to improve the query efficiency and the privacy of the query.The main research work will be focused on the following three points as follows:(1)Characteristics of the existing three kinds of protection location privacy technology:location anonymous,location anchor and spatial transformation.This paper focuses on PIR protection location privacy and points out the existing query methods'which based on PIR technology shortcomings.(2)Do propose a location privacy search method PRN kNN based on privacy information retrieval.The novel query technology overcomes heavy time cost in preprocessing as well as the poor dynamic query plan.Also it enhances the effectiveness of location privacy protection.(3)To aim to surmount the shortcomings of the PRN_kNN in personalized setting and flow control,The algorithm PNC_kNN is proposed to improve the effectiveness of PRN kNN.The custom settings ensure the efficiency of the query and meet the individual needs of query.Theoretical analysis and experiment result demonstrate the effectiveness of the proposed technique.