Abstract
Wireless Sensor Networks (WSNs) are often deployed in remote and hostile areas and because of their limited power and vulnerability, the sensors may stop functioning after sometime leading to the appearance of holes in a network. A hole created by the non-functioning sensors in turn severs the connection between one side and the other side of the network and alternative routes need to be found for the network traffic. Prior research tackled the holes problem only when packets reach some nodes near the hole. In this case, the feedback packets are generated and accordingly the data packets need to be rerouted to avoid the holes. The traffic overhead for rerouting consumes additional battery power and thus increases the communication cost as well as reducing the lifetime of the sensors. To deal with the dynamical changes in network topologies in an autonomous manner, ant colony optimization (ACO) algorithms have shown very good performance in routing the network traffic. In this paper, we analyze the scalability and stability of the ACO-based routing protocol BIOSARP against the issues caused by holes in WSNs. Network simulator 2 (ns-2) is utilized to perform the analysis. Findings clearly demonstrate that BIOSARP can efficiently maintain the data packet routing over a WSN prior to any possible holes problems, by switching data forwarding to the most optimal neighboring node.