Abstract
Industrial Internet of Things (IIoT) is one of the most trending topics in the present world. It has numerous benefits and its potentiality is unfolding gradually. The implementation of IIoT in mission and safety-critical systems has shown its significance. Since it deals with important and sensitive information, an extensive study is required to address the susceptibility of it towards security issues. Therefore, there have been many proposals to use certificateless signature scheme, machine learning approaches, public key encryption as well as blockchain to improve the security of IIoT. It is important to note that blockchain is playing a significant role in the IIoT technology where the important characteristics of blockchain, immutability, decentralization, tamper-proof, have made a profound impact on the security vulnerabilities of IIoT. Taking this into account, this paper proposes a permissioned blockchain for IIoT that addresses and guarantees to ensure and improve the security vulnerabilities and susceptibility of IIoT towards cyber threats. The permissioned blockchain enabled IIoT ensures a secure medium for device communication, data sharing, and access control. This paper also discusses the security issues of IIoT and presents a comprehensive analysis of some of the proposed blockchain based solutions to improve IIoT security challenges. It addresses the benefits of a permissioned blockchain enabled IIoT over a public blockchain as well as presents a future direction for the upcoming integration of blockchain with IIoT and other industries.