Forensic Verification of Health Data From Wearable Devices Using Anonymous Witnesses

The use of wearable devices, such as smartwatches, glasses, clothes, and fitness bracelets is increasing at an ever-growing pace. Major corporations and insurance companies have started mandating their use for their employees and clients. Data from such devices have begun to feature in settlement claims and as evidence in courts as well, requiring it to be irrefutable and tamper-proof. Lack of protection for personal data as well as the contextual information such as location tracking and its use by law enforcement agencies is raising serious privacy concerns among the general public and civil liberty advocates. In this article, we propose a novel scheme to secure the wearable sensor's communication through its crowdsourced logging by neighboring wearable and smart devices called witnesses preserving the contextual information (such as time and location) as well. To ensure witness privacy, gateway and witness devices use the reciprocity property of wireless medium between them to generate pairs of closely matching link signatures, which not only provide the proof of presence for the witnesses in the vicinity but also act as their time-varying pseudonyms. We demonstrate the feasibility and efficacy of our scheme through the prototype implementation using real wireless devices, and via simulation and experimental results.