Adapting broadcasting sets to topology changes in packet radio networks

Most existing algorithms that maximize throughput in packet radio networks by selecting a maximal broadcasting set in each time slot of a TDMA frame cannot accommodate changes in the topology of the network. In fact, when there is a change in the network topology, these algorithms have to be rerun for the entire network to compute a new broadcasting set. This is certainly time and bandwidth consuming. In this paper, we show that the problem of adapting a maximum broadcasting set to a simple topology change in packet radio networks is NP-complete. We then propose a new heuristic that adapts a given broadcasting set to topological changes caused by the addition of new radio stations to the network. We do some experiments to show that the performance of our heuristic is almost as good as rerunning the original heuristic for the entire network. We also discuss a distributed implementation of our heuristic.