A Secure MQTT Framework from PUF-based Key Establishment

In this paper, we first propose a PUF-based key establishment (KE1+) protocol because PUFs (Physically Unclonable Functions) can be an alternative to perfect tamper-resistant modules, and a better solution to provide security against side-channel attacks. The KE1+ protocol (an improved version of KE1 [33]) additionally provides mutual authentication and efficiency optimization for client side. Then, we propose a secure MQTT framework (for short, S-MQTT) where the KE1+ protocol is executed for key establishment whenever needed between publishers/subscribers and a broker. This S-MQTT does not require any certificate validation/revocation checks on both publishers/subscribers and broker sides which can simplify the initial setup of publishers/subscribers. Also, we explain implementation details and performance overhead of S-MQTT that makes use of MQTT open source project Mosquitto 1.4.10 [20]. With average processing times of S-MQTT publisher, we show that S-MQTT publisher is much more efficient than the previous work [34].