Most current privacy-reserving located-based service (LBS) techniques have proved to be quivering in the balance with the levels of privacy protection and communication overhead. In order to address these challenges, an adaptive collaborative privacy-preserving technique was introduced in which mobile user firstly achieves his location context based on the downloaded rough topology maps from LBS provider's server while user consume services, then regionalizes his original position and selects a collaborative proxy user for adaptive context-aware incremental nearest-neighbor querying. Meanwhile, in order to improve the QoS (quality-of-service) of system, the query-anchor was determined by communication cost-estimation method and POIs(points of interest) were filtered by on proxy user,which eliminate communication overhead of whole service process. Theoretical analysis and experimental results validated the technique’s effectiveness on LBS accuracy, privacy protection and communication QoS compared with SpaceTwist.
