Design and Performance Evaluation of Overhearing-Aided Data Caching in Wireless Ad Hoc Networks

Wireless ad hoc network is a promising networking technology to provide users with Internet access anywhere anytime. To cope with resource constraints of wireless ad hoc networks, data caching is widely used to efficiently reduce data access cost. In this paper, we propose an efficient data caching algorithm which makes use of the overhearing property of wireless communication to improve caching performance. Due to the broadcast nature of wireless links, a packet can be overheard by a node within the transmission range of the transmitter, even if the node is not the intended target. Our proposed algorithm explores the overheard information, including data request and data reply, to optimize cache placement and cache discovery. To the best of our knowledge, this is the first work that considers the overhearing property of wireless communications in data caching. The simulation results show that, compared with one representative algorithm and a naive overhearing algorithm, our proposed algorithm can significantly reduce both message cost and access delay.