by Ghassan Samara, Eyad A. Shaban, Hasan Al-Refai, Mohammed Aman, Mahmoud Odeh, Mehmet Kemal Özdemir, Bandar Z. Altubaishe
ABSTRACT
Wireless Sensor Networks (WSNs) represent a fundamental part of current Internet of Things (IoT) systems, allowing for constant monitoring in smart cities, the environment, and industrial systems. However, a fundamental limitation of these networks over long-term operation is uneven energy consumption and the energy-hole problem that arises around a static sink. To address these issues, this paper presents PSO-MSM, a sustainability-oriented communication protocol that combines multi-objective Particle Swarm Optimization (PSO) and adaptive mobile sink mobility. The protocol optimizes cluster head (CH) selection and dynamically adjusts the sink’s trajectory through multi-radius circular paths to balance the forwarding load across the sensing field. Optimization is performed jointly with consideration of residual energy, intracluster compactness, and the proximity of each CH to the sink. This coordinated clustering-mobility design reduces long-distance transmissions, relieves hotspot depletion, and improves overall energy sustainability. Extensive ns-3 simulations demonstrate that PSO-MSM significantly enhances network lifetime, increasing the time to first-node-dead, half-nodes-dead, and last-node-dead events by 46% compared with LEACH, HEED, and PEGASIS. The protocol also achieves higher residual energy, improved packet delivery ratio, reduced endto-end delay, decreased channel congestion, and significantly lower energy imbalance. These results indicate that PSO-MSM provides an effective solution for smart city and IoT deployments, offering reliability, reduced maintenance, and improved sustainability for long-term operations where these issues are a major priority.
