Localized minimum spanning tree based multicast routing with energy-efficient guaranteed delivery in ad hoc and sensor networks

We present a localized geographic multicast scheme, MSTEAM, based on the construction of local minimum spanning trees (MSTs), that requires information only on 1-hop neighbors. A message replication occurs when the MST spanning the current node and the set of destinations has multiple edges originated at the current node. Destinations spanned by these edges are grouped together, and for each of these subsets the best neighbor is selected as the next hop. This selection is based on a cost over progress metric, where the progress is approximated by subtracting the weight of the MST over a given neighbor and the subset of destinations to the weight of the MST over the current node and the subset of destinations. Since such greedy scheme may lead the message to a void area (i.e., no neighbor providing positive progress), we propose a new multicast generalization of the well-known face recovery mechanism. We provide a theoretical analysis proving that MSTEAM is loop-free, and achieves delivery of the multicast message as long as a path to the destinations exists. Our results demonstrate that MSTEAM outperforms the best existing localized multicast scheme, and is almost as efficient as a centralized scheme in high densities.