Analysis of the Impact of Swarm Mobility on Performance of Routing Protocols in MANETs

In a mobile ad-hoc network (MANET), node mobility has a significant impact on the performance of routing protocols. Most of the previous research has been focused on entity mobility models, i.e., movements of the mobile nodes are independent of each other. In this paper, we investigate the impact of swarming behavior of mobile nodes, as observed in many mobile networks, on the performance of MANET routing protocols. The effects of coordinated movements of mobile nodes are characterized by using a Markov chain, through which a quantized collaboration degree is defined. Based on the swarm mobility model, we analyze the probabilistic properties of hop count as a complement to those analytical studies on packet delay performance. With a medium access control model, we derive an upper and a lower bound of routing overhead for MANET proactive routing protocols. Simulations are used to demonstrate the validity of the derived analytical expressions. Numerical and simulation results show that more coordinated movements of the nodes reduce the number of control packets required to be disseminated over the network, and in turn the routing overhead.