A Message Processing Method for Top-k Query for Traffic Reduction in Ad Hoc Networks

In ad hoc networks, to acquire only necessary data items, it is effective that each mobile node retrieves data items using a top-k query, in which data items are ordered by the score of a particular attribute, and the query-issuing mobile node acquires data items with the k highest scores. In this paper, we propose a message processing method for a top-k query for reducing traffic and keeping the accuracy of the query result, i.e., guaranteeing that data items with the k highest scores in the entire network are acquired. When a mobile node transmits query and reply messages, our method can be used to reduce candidates of data items included in the top-k result to prevent unnecessary data transmissions. Moreover, if a mobile node detects a disconnection of a radio link, it searches for an alternative path to transmit the reply message to the query-issuing node. We present simulation results to evaluate the performance of our proposed method.