MPO: MQTT-Based Privacy Orchestrator for Smart Home Users

Security and privacy concerns present the most significant obstacles to consumer adoption of Internet-of- Things (IoT) devices. A lack of transparency and control complicates user trust in IoT. Additionally, a growing history of misuse and abuse exists in IoT. Notably, smart TVs have periodically scanned and collected users' private information without consent. Due to a hybrid of distributed ecosystems within IoT, users cannot easily implement traditional access control over their devices as data flows within different nodes for storage and processing. We propose MQTT-Based Privacy Orchestrator (MPO) to implement traditional access control on IoT devices. MPO enforces privacy preferences by implementing access control at an MQTT broker. We open-source and provide MPO as an add-on to the popular Home Assistant open-source home automation framework to support widespread adoption. We conducted experimental evalu-ations to validate the functionality and examine the performance of MPO. Our performance evaluation generated more than 16,686 messages, which MPO delivered in under a second. Our work demonstrates a practical solution to facilitate users' privacy preferences and enforce access control for MQTT-based devices.