Blockchain for Internet of Things

Abstract

Internet of Things (IoT) technology is digitizing the physical world by connecting enormous and heterogeneous devices and unleashing great economic benefit. However, data privacy, security and trust issues in current solutions are seriously limiting the adoption of IoT applications. Blockchain, a decentralized and tamperresistant ledger, maintains consistent and immutable blocks of data at different servers and has the potential to tackle the security concerns in IoT applications. Inherent features in IoT, such as the massive IoT devices, heterogeneous IoT networks, limited battery, low computing power and communication bandwidth, make it hard to directly adopt blockchain technology in IoT application. This chapter presents a comprehensive survey on existing blockchain and IoT technologies and emphasizes on the challenges and limitation. Current studies, projects and designs on Blockchain-IoT systems are introduced and compared to illustrate the feasibility of the integration of blockchain and IoT. Blockchain technologies that can potentially address the critical challenges in IoT applications and suit the features of the same are identified with potential adaptations and enhancements elaborated on blockchain data structures, key blockchain technologies and consensus protocols. Future research directions of blockchain are collated for effective adoption in IoT applications.