Energy Consumption Benchmarking of Post-Quantum Cryptography on Resource-Constrained IoT Nodes

The rapidly increasing number of Internet of Things devices and the forthcoming arrival of quantum computing is imposing the transition to new quantum-resistant cryptography in constrained-resources devices. However, the energy impact of post-quantum cryptography on wireless sensor networks, critical to battery life and network up-time, remains largely unquantified. In this paper, this gap is addressed by evaluating the energy impact of standardized post-quantum cryptography CRYSTALS-Kyber and FALCON on extreme edge Internet of Things devices. In this work a new energy aware multilevel security framework over Contiki-NG has been developed and tested on extreme edge nodes based on EFR32MG12 Cortex-M4 System-on-Chip. This work provides energy consumption data measured in four different operational scenarios during one-hour experiments, allowing to estimate the impact on battery lifetime for four different battery capacities: 125, 225, 500 and 1000 mAh. The results presented in this work demonstrate that while the highest security level offers post-quantum confidentiality and integrity incurs in measurable costs, leading to a maximum lifetime reduction lower than 1% in the experiments with FALCON being identified as the dominant contributor to energy consumption related to post-quantum cryptography. At intermediate security levels, only post-quantum confidentiality using CRYSTALS-Kyber can be achieved at considerably lower energy costs. This study provides quantitative evidence supporting the feasibility of deploying post-quantum cryptography in resource-constrained wireless sensor networks through a novel energy-aware approach, offering crucial data for designing secure and sustainable quantum-resistant Internet of Things systems.