A Dissemination Analysis in Mobile Wireless Ad Hoc Networks Using Probabilistic Broadcast

Broadcast schemes play an important role in the performance of mobile ad hoc networks. They are widely used as a dissemination mechanism and as a part of the discovery phase of routing protocols. The simple flooding algorithm is the usual mechanism employed in mobile ad hoc networks, but it has been demonstrated its inefficiency in congested scenarios due to the high number of collisions and contentions. These problems can be partially alleviated by using a probabilistic broadcast scheme in which every node forwards the incoming packets according to a certain forwarding probability. In this paper we use the simple probabilistic broadcast scheme to evaluate the effects of congestion on the performance of broadcasting in ad hoc networks through a mediation analysis. We hypothesize that the congestion mediates in the relationship between the forwarding probability (independent variable) and the output metric (dependent variable). The simulation results prove the existence of the mediating effects and how such effects are counterbalanced depending on the target use of the probabilistic broadcast scheme.