Blockchain‐Driven Internet of Things

Blockchain has been regarded as a promising technology for IoT because it provides significant solutions for decentralized networks that can address trust and security concerns, high maintenance cost problems, and so on. The decentralization provided by blockchain can be largely attributed to the use of a consensus mechanism, which enables peer‐to‐peer trading in a distributed manner without the involvement of any third party. This chapter starts by introducing the basic concepts of blockchain and illustrating why a consensus mechanism plays an indispensable role in a blockchain‐enabled IoT system. Then, we discuss the main ideas of two famous consensus mechanisms, PoW and PoS, and list their limitations in IoT. After that, we introduce Practical Byzantine Fault Tolerance (PBFT) and Direct Acyclic Graph (DAG) based consensus mechanisms as an effective solution. Next, several classic scenarios of blockchain applications in the IoT are introduced. The potential issues and challenges of blockchain in IoT to be addressed in the future are discussed in the last section.