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A Comprehensive Survey on Blockchain in Industrial Internet of Things: Motivations, Research Progresses, and Future Challenges

With rapid development of enabling technologies such as Internet of Things, robotics, and big data, the fourth industrial revolution known as “Industry 4.0” (I4.0) has become a great opportunity for productivity innovation around the world. Industrial Internet of Things (IIoT), as a typical implication of Cyber-Physical Systems (CPS) in I4.0 era, has attracted significant attention. It aims at optimizing resources and improving production efficiency for manufacturing industry through deep interconnection of physical equipment, wide collection of multi-dimensional data, intelligent awareness of environment and automatic control. Blockchain is a kind of distributed ledger technology and has features including decentralization, anti-tamper, transparency, anonymity, and contract-autonomy. These features are helpful to improve the services and promote the development of IIoT. In this paper, we provide a comprehensive survey on the literatures applying blockchain technology into IIoT. We firstly introduce the related works and background knowledge. And then, the motivations and benefits for applying blockchain into IIoT are discussed in detail. Furthermore, based on the layered architecture of blockchain we summarized in the previous work, we outline the research framework of blockchain in IIoT. Meanwhile, the related application research is presented from the perspectives of devices security, data collection and sharing, and industrial application. Moreover, we explore the technical requirements of blockchain platforms in IIoT applications. Finally, some challenges and future directions on blockchain in IIoT, as well as broader perspectives, are concluded for further study.