Robust multicasting using an underlying link state unicast protocol

In order for mobile ad-hoc networks (MANETs) to be a viable alternative to infrastructured wired and wireless networks, efficient reliable multicast protocols need to be established. In this paper, we propose a Robust Multicast Routing algorithm (RoMR), for ad-hoc networks. In order to increase reliability, RoMR builds multiple trees from a sender to each of the receivers in the multicast group. A novel technique to predict the likelihood that a link will continue to exist into the next time span is based on successive power levels of the received signal from neighboring nodes. These predictions are used during the creation of the multicast trees. Another unique aspect of RoMR is that links that are predicted to be less prone to failure than other links may be shared among several trees. Forward error correcting coding techniques reduce the total number of extra packets added to the original data packets from the source into the network increasing the efficiency of protocol.