Minimum Multicast Time Problem in Wireless Sensor Networks

Abstract

AbstractGiven an undirected graph representing a network of processors, and a source node needs to broadcast a message to all other nodes in the graph, the minimum broadcast time problem is to find a scheme that accomplishes the broadcast in a minimum number of time steps under the constraint that at each time round, any node can send the message to at most one of its neighbors in the network. This NP-complete problem has been extensively studied in literature.In this paper, we consider a generation of the minimum broadcast problem, the minimum multicast time problem, in unit disk graphs which model wireless sensor networks. The goal is to multicast a message from the source node to a set of specified sensor nodes of the network in a minimum number of time rounds. We prove that this problem is NP-complete, and give an O(1)–approximation algorithm for it. Our simulation results show that the practical performance of the proposed algorithm is much better than the theoretically proved approximation ratio.KeywordsSensor NodeWireless Sensor NetworkApproximation AlgorithmSource NodeTransmission RangeThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.