Optimization of K-NN Query Processing in Road Networks Using Frequent Query Retrieval Table

Location Based Services has been widely used to guide the user with real time information. The efficient query processing and preserving the privacy of the user is a key challenge in these applications. There have been many researches for anonymity in the spatial network by generating cloaking region in the Road networks and a K-NN algorithm is used for processing query in this region. If the same query is issued frequently and processing these queries continuously is an issue. In this paper, a novel Frequent Query Retrieval Table (FQRT) is proposed to increase the efficiency of query processing in the K-NN algorithm. FQRT maintains the results of the frequently occurring queries and can be retrieved when the same query is issued in the cloaking region. The proposed FQRT algorithm reduces the query processing time and the network expansion cost.