Gateway-assisted hybrid region-based multi-hop routing for sustainable IoT sensor deployments

Wireless sensor networks (WSNs) are a cornerstone of internet-of-things (IoT) applications but remain constrained by the limited energy resources of sensor nodes, particularly during data transmission. This paper proposes a hybrid, multi-hop routing protocol, gateway-assisted multi-hop enhanced stable election protocol (M-GESEP), designed to extend network lifetime in WSN-based IoT systems. The sensing field is partitioned into three logical regions: (i) Base station region (BR), (ii) Gateway region (GR), and (iii) Cluster region (CR). A hybrid communication strategy is employed, whereby nodes in BR and GR transmit data directly, while nodes in CR utilise cluster-based communication. This region-aware design reduces long-distance transmissions and balances the forwarding load, thereby minimising energy consumption. Simulation results demonstrate that M-GESEP significantly enhances network lifetime compared to established baselines, achieving improvements of 74%, 58.2%, 11.1%, 34.5% and 13.3% relative to SEP, EDEEC, ESEP, EAGBRP, and HMGEAR, respectively, under identical settings. The results indicate that integrating gateway-assisted multi-hop routing with selective clustering provides a practical and efficient solution for energy-aware WSN deployment. The proposed protocol offers a clear, implementable framework for partitioned topologies and informs future developments in large-scale, heterogeneous IoT networks.