Gateway-based multicast protocol - a novel multicast protocol for mobile ad hoc networks

Multicasting in mobile ad hoc networks (MANETs) poses several challenging problems. Though a number of multicast protocols for MANETs exist in the literature, there are many areas where improvements are desirable and possible. A new multicast protocol is proposed for MANET, called the gateway-based multicast protocol (GBMP) that seeks to improve upon the existing protocols in terms of the speed and the cost of the multicast tree repair mechanism, the transmission efficiency and the amount of control overhead. GBMP achieves these improvements by using a number of novel features, such as both global and local maintenance of group-shared trees, a bidirectional multicast tree repair mechanism and the suppression of unnecessary acknowledgments. In addition, we have introduced a new metric called weighted occurrence of consecutive packet loss to measure the discontinuity in data packet delivery. Extensive simulation study shows that GBMP outperforms the more established ODMRP and ADMR protocols in a number of important performance metrics under different traffic patterns and source node counts.