Analysis of leveled probabilistic routing in mobile ad hoc networks

In mobile ad hoc networks (MANET), some mobile hosts may be outside the range of the source node. In order to deliver the message to those hosts, intermediate nodes should relay the packets for them. Due to the node mobility, we cannot have a fixed group of mobile nodes perform the task of packet relaying. In this paper we propose a routing protocol based on the preassigned probability model. In this protocol, a mobile host probabilistically sends the relay packets (rebroadcasts) according to its neighborhood information. We exploit the "HELLO" message exchanges between immediate neighbors to obtain the neighborhood information. Using this method, we can reduce routing cost by minimizing the number of rebroadcasts in route discovery period without a significant impact on the network connectivity. Moreover, the chance of contention and collision among neighboring nodes is also reduced. As a result, the overall network performance is improved, while higher goodput and lower energy consumption is achieved. Our approach categorizes mobile hosts into four groups according to their neighborhood information. For each group of nodes, we assign a specified value of rebroadcasting probability. The mobile hosts with more neighbors are given higher rebroadcasting probability, while the mobile hosts with fewer neighbors have a lower rebroadcasting probability. Analytical results show that our approach outperforms the AODV protocol.