Optimum Routing Approach vs. Least Overhead Routing Approach for Minimum Hop Routing in Mobile Ad hoc Networks.

Proactive routing protocols for mobile ad hoc networks (MANETs) follow on Optimum Routing Approach (ORA) to choose and use the optimal route at any time instant. On the other hand, on-demand routing protocols for MANETs have been traditionally designed using the Least Overhead Routing Approach (LORA) wherein a route determined using broadcast flooding-based route discovery is used as long as exists. With LROA, a route determined to be the best optimal route based on a particular route selection metric, may later become sub-optimal, and could be still used, if exists. In this paper, we evaluate the impact of the ORA and LORA strategies on minimum hop routing. Our hypothesis is that the LORA strategy could yield routes with a larger time-averaged hop count when compared to the minimum hop count of routes determined using the ORA strategy. We evaluate the two routing strategies under diverse conditions of network density, node mobility and mobility models such as the Random Waypoint model, City Section model and the Manhattan model. Simulation results illustrate that the hop count of routes maintained according to the LORA strategy is at most 12% greater than that incurred with the ORA strategy. The Random Waypoint model under the LORA strategy incurs the lowest hop count per path and the largest increase in hop count vis-à-vis the ORA strategy; on the other hand, the Manhattan model incurs a larger hop count per path and the smallest increase in hop count. [ABSTRACT FROM AUTHOR]