A Systematic Review of Internet of Things Routing Protocols with Clustering and Technique for Order of Preference by Similarity to Ideal Solution (2010–2025)

The Internet of Things (IoT) broadly refers to interconnected objects and devices that can be monitored and controlled via Internet-enabled applications. Despite its rapid growth, IoT networks face significant challenges in ensuring reliable communication and efficient energy utilization, due to factors such as dynamic topology, resource constraints, and heterogeneous network environments. Routing, in particular, remains a critical concern, as conventional protocols often fail to deliver the performance required for large-scale, resource-limited IoT deployments. Energy scarcity at sensor nodes and the need to minimize multi-hop transmissions to the sink node necessitate the design of energy-aware routing algorithms capable of reducing latency and extending network lifetime. This review systematically analyzes recent routing approaches—emphasizing clustering-based methods and multi-criteria decision-making techniques such as TOPSIS—by examining their operational principles, advantages, and limitations. The findings highlight emerging trends and research gaps, with a focus on integrating clustering and TOPSIS weighting methods to improve routing performance in next-generation IoT systems.