Privacy engineering in Smart Home (SH) systems: A comprehensive Privacy Threat Analysis (PTA) and risk management approach

Addressing trust concerns in Smart Home (SH) systems is imperative due to the limited study on privacy preservation approaches that focus on analyzing and evaluating privacy threats for effective risk management. While most research focuses primarily on user privacy, device data privacy, especially device data that can reveal the identity of a smart device, is almost neglected. Moreover, a breach of device data could indirectly reveal the user data, as these smart devices store, process, and transmit user and device data within the SH system. To this end, our study incorporates Privacy Engineering (PE) principles in the SH system that considers user and device data privacy, leveraging the LINDDUN PRO Privacy Engineering (PE) framework. In the first stage of the LINDDUN PRO PE framework, we present a DFD based on a typical SH reference model to better understand SH system operations. To identify potential areas vulnerable to privacy threats in the SH system, we conduct a Privacy Threat Analysis (PTA) using the LINDDUN PRO threat model in the second stage. In the third stage, a Privacy Impact Assessment (PIA) was conducted to manage privacy risks by prioritizing privacy threats based on their likelihood of occurrence and potential consequences. Finally, we suggest possible Privacy-Enhancing Technologies (PETs) that can mitigate some of these privacy threats. Furthermore, we validate the impact of implementing PETs to minimize the privacy risks in the SH system. This study aims to elucidate the primary privacy threats in SH systems, their associated risks, and the prioritization of these threats in SH systems, as well as the effect of PETs implementation on the SH system. The outcomes of this study are expected to benefit SH stakeholders, including vendors, cloud providers, users, researchers, and regulatory bodies in the SH systems domain.