Optimal allocation of clients to replicated multicast servers

In this paper we investigate multicast server selection problems. First we give a definition of the static multicast server selection problem, in which we assume a set of static clients and multicast servers and consider how one might produce an optimal allocation of the clients to the servers. We use a transformation method for deriving multicast server selection algorithms from traditional multicast routing algorithms. To investigate the dynamic behavior of client join and leave and the cost incurred during the process, we next define the dynamic multicast server selection problem, in which the clients join and leave the multicast session dynamically. The goal is to produce an optimal allocation of clients to servers with an emphasis on how this allocation behaves over time. We formulate the problem as a Markovian decision process (MDP). Our analysis of the problem leads to two heuristics which we use to propose a simple selection algorithm. Our simulation compares the performance of our proposed algorithm with other multicast server selection algorithms.