: A reliable multicast algorithm, called RMA, for mobile ad hoc networks is presented that is based on a new cost criterion, called link lifetime, for determining the optimal path between a pair of nodes. The algorithm has the characteristics of using an undirected graph for its routing operations rather than a fixed structure like a tree or a mesh. Previously proposed routing metrics for mobile ad hoc networks were designed for use in wired environments, where link stability is not a concern. We propose a new metric, called the lifetime, which is more appropriate for mobile ad hoc networks. The lifetime metric is dependent on the predicted future life of the link under consideration. We developed a simulator for the mobile ad hoc networks, which is portable and scalable to a large number of nodes. Using the simulator, we carried out a simulation study to analyze the effectiveness of the routing metrics and the performance of the proposed reliable multicast algorithm. The simulation re...