EDCC-RPL: A novel energy-efficient and load-balanced objective function for RPL Routing in IoT networks enhancing network lifetime and reliability

Energy efficiency and balanced load distribution remain persistent challenges in the Routing Protocol for Low-Power and Lossy Networks (RPL), significantly affecting the lifetime and reliability of Internet of Things (IoT) deployments. This study introduces EDCC-RPL, a novel multi-metric objective function that integrates Expected Transmission Count (ETX), end-to-end delay, and child count through an adaptive additive model. Unlike conventional single or dual metric schemes such as OF0, MRHOF, and EA-EPL, EDCC-RPL simultaneously enhances energy efficiency, network stability, and scalability. Extensive simulations in Contiki Cooja with 20-50 nodes demonstrate up to 32% lower energy consumption, 18% higher Packet Delivery Ratio (PDR), and 50-60% reduction in parent switching (churn) in dense topologies. These improvements validate EDCC-RPL's novelty in achieving joint optimization of reliability, delay, and load balancing. The proposed approach provides a practical and scalable solution for sustainable IoT networks in smart cities, industrial monitoring, and environmental sensing applications. The implementation code of the proposed EDCC-RPL algorithm is publicly available at https://github.com/drmasifhabib/edcc-rpl-github for reproducibility and reuse.