POMA: Prioritized Overlay Multicast in Ad Hoc Environments

摘要

Overlay Multicast networks in mobile ad-hoc environments have received much attention due to their increasing number of practical applications. In many applications, some participating nodes might be members of more than one overlay trees or may wish to build a temporary tree in order to perform certain important tasks. The priority of these trees can be defined by the importance of the service. For the success of such an application, it is necessary that nodes belonging to more than one tree are smart enough to ignore incoming messages from members in low priority trees while they are listening to members from a higher priority tree. In this paper, we present a prioritized overlay multicast in ad-hoc environments (POMA). POMA builds priority trees with certain nodes carrying important tasks in overlay networks, and rearranges low priority trees whenever some nodes temporarily move to a high priority network. We study the feasibility of POMA by identifying a suitable unicast routing protocol, exploring to use location information to build efficient trees, and studying the impact of density of wireless nodes to the system performance.