Fuzzy Logic Aided Dynamic Source Routing in Cross-Layer Operation Assisted Ad Hoc Networks

The classic Dynamic Source Routing (DSR) protocol opts for the route requiring the lowest number of hops for transmitting data from the source to the destination. However, owing to node mobility in dynamic self-organizing ad hoc networks, the route containing a low number of potentially long-range hops does not always perform well. Furthermore, the currently used route may break owing to node-mobility and the routing information gathered during route discovery may become invalid. In order to circumvent the potentially inaccurate nature of the routing information, a fuzzy logic aided technique is incorporated into the routing algorithm for mitigating the influence of imprecise routing information. As a further benefit, fuzzy logic aided techniques are capable of processing multiple inputs, hence we use both the expected route lifetime and the number of hops as its input parameters, which allows us to integrate the physical layer and network layer into a jointly designed routing protocol. The route life-time is typically reduced with the increased mobility of the nodes. The specific route having the highest route ´stability´ is finally selected for data transmission, and based on the route life-time the route-cache expiration time is adjusted adaptively. We will demonstrate that the proposed fuzzy logic based DSR outperforms the conventional DSR in terms of the attainable network throughput, despite having a lower network control load. Finally, we quantify the impact of the physical layer on the achievable performance of the network layer for different physical layer schemes by using the OMNeT++ simulator.