Post-Quantum Lightweight Key Sharing Protocol for Secure MQTT-Based IoT Networks

The Post-Quantum Lightweight Key Sharing Protocol for Secure MQTT-Based IoT Networks (PQLKS-MQTT) addresses the critical need for quantum-resistant and resource-efficient security in IoT communications. As the proliferation of IoT devices continues, securing MQTT-based networks against evolving threats, including quantum attacks, becomes imperative. PQLKS-MQTT integrates the Kyber Key Encapsulation Mechanism for post-quantum key exchanges, along with BLAKE2s hashing and ChaCha20 encryption, to ensure robust security with minimal resource consumption. Implemented using the Cooja simulator with Contiki OS, Eclipse Mosquitto MQTT broker, and Open Quantum Safe (liboqs) library, the protocol demonstrates superior performance compared to state-of-the-art solutions. Experimental results show that PQLKS-MQTT achieves the lowest CPU energy consumption (0.0000021 mJ), fastest execution time (0.35 seconds), and minimal computational (260 CPU cycles) and communication overheads (55 bytes), with only a slight increase in average energy consumption (0.00145 mJ) due to post-quantum cryptographic operations. This balance between enhanced security and efficient resource utilization makes PQLKS-MQTT a suitable solution for resource-constrained IoT devices and large-scale deployments, offering a scalable, quantum-safe communication framework for future IoT ecosystems.