Multicast routing protocol for ad-hoc networks with route aggregation and transmission power control

In this paper, we propose a multicast routing protocol for ad-hoc networks to reduce packet collisions. Packet collisions are one of the degradation factors in wireless communications. In the ad-hoc multicasting, some forwarder nodes forward data packets from a source node to a lot of destination member nodes. Moreover, forwarding timing of data packets is almost same instance because forwarder nodes with a same hop count receive data packets at same instance from their an upstream node. Therefore, the ad-hoc multicasting tends to suffer from packet collisions due to multiple forwarding of data packets at same instance. In the proposed routing protocol, each forwarder node informs a number of its downstream nodes. Then, neighbor downstream nodes select a forwarder node with maximum number of downstream nodes to aggregate multicast routes. Hence, the proposed protocol can reduce redundant packet forwarding due to a lot of existence of forwarder nodes. Additionally, forwarder nodes control transmission power of data packets according to information from downstream nodes. As the results, the proposed protocol can reduce packet collisions due to hidden terminal problems. From the simulation results, we can find that the proposed protocol can reduce the packet collisions and improver the delivery ratio.