How do forwarding schemes influence the multi-hop connectivity in cognitive radio ad-hoc networks?

This paper investigates the influence of forwarding scheme on multi-hop connectivity in cognitive radio ad-hoc networks (CRAHNs). We study three different forwarding schemes, i.e. a full flooding scheme and two limited flooding schemes with forwarding angles α = 60° and 90°. The multi-hop connectivity of cognitive radio ad-hoc networks under each forwarding scheme is examined and compared to each other. Simulation results in this paper show that full flooding only outperforms other schemes under certain circumstances of secondary user´s density and operating frequency. However, it is a well-known fact that full flooding results in more network resource usage than limited flooding. Therefore, this paper provides an efficient guidance for system designers to characterize and optimize the multi-hop connectivity of CRAHNs under certain packet forwarding schemes of routing protocols so that maximum connectivity can be achieved with lowest network resource usage.