An enhancement in directed diffusion and AOMDV routing protocols using hybrid intelligent systems

The Wireless Sensor Networks (WSNs) are composed of small sensor nodes capable of sensing (collecting), processing and transmitting data related to some phenomenon in the environment. Despite the numerous possibilities of use, the WSN has serious constraints, mainly related to the energy consumption during data transmission. These constraints require the implementation of enhancements in routing protocols that enable the sensor nodes to communicate efficiently and effectively with minimum power consumption. In our proposal, a fuzzy system is used to estimate the route quality based on the number of hops and the energy level of the nodes that compose a route. The estimated route quality is used by the routing protocol for selecting a specified path to send a message. An Ant Colony Optimization (ACO) algorithm is used to adjust, in an automatic way, the rule base of the fuzzy system in order to enhance the estimation of the route quality, hence increasing the energy efficiency of the network. The simulations, using the Directed Diffusion (DD) and Ad-Hoc On-Demand Multipath Distance Vector (AOMDV) multipath routing protocols, showed that the proposal is effective from the point of view of important metrics related to WSNs such as: number of messages delivered to the sink node, average cost of message, packet loss rate, and time of death of the first sensor node.