BCHealth: A Novel Blockchain-based Privacy-Preserving Architecture for IoT Healthcare Applications

The advancements in networking technologies have introduced the Internet of Everything (IoE) and smart living concepts. The main idea behind making everything smarter is to improve individuals’ quality of life. An excellent example of such a technology is smart healthcare which provides efficient, sustainable, and real-time human services. However, data security and privacy are among the most important challenges of smart healthcare applications. Blockchain (BC) has been considered as a promising solution for the secure management of healthcare data due to its immutability and transparency features. However, there is a trade-off between transparency and user data privacy which is a prominent challenge in adopting BC for healthcare applications. Some researchers have considered user data privacy and proposed a few solutions; however, data owner's access control desire has not been considered in the state-of-the-art models. In this paper, to overcome the trade-off challenge between transparency and access control, we propose an architecture (so-called BCHealth) that enables data owners to define their desired access policies over their privacy-sensitive healthcare data. BCHealth is composed of two separate chains for storing access policies and data transactions. We address the real-world development challenges of BC, i.e., scalability, delay, and overhead, by adopting a clustering approach. Our extensive experimental analysis proves the efficiency of BCHealth (in terms of computation and processing time) and its resilience against several security attacks.