Blockchain-Based Mechanisms to Address IoT Security Issues: A Review

Abstract

Internet of things (IoT) is seen as combinations of various communication technologies and embedded equipment such as sensors, micro-controllers, radio-frequency identification, wireless devices, etc., which work as a single unit to achieve a specific task in a smart way, i.e., with less human intervention, and decisions are made automatically. IoT is used in many sectors such as smart home automation, smart grids, smart cities, vehicular networks, etc. Due to easy accessibility and reachability to such devices or networks, there are severe security and privacy issues in IoT. User authentication, access control mechanism, confidentiality and data correctness are a few of the major concerns among them. Though it looks like conventional security concerns, but due to (i) the dynamic nature of IoT, (ii) the resource-scarce nature of the devices and (iii) different standards and communication stacks involved, traditional network security countermeasures may not be applied directly to IoT. In recent years, usage of blockchain technology to address various security issues, specifically data correctness, has opened up a facet for IoT to explore the option of using blockchain in IoT. Researchers have started investigating the same. Primitively, blockchain is a non-editable, decentralized and cryptographically secured ledger that is tolerant against byzantine failure. This nature of blockchain makes it an attractive alternative to address security issues such as data integrity, entity authentication, etc. Also, in an IoT environment, where devices are spread across a vast geographical area, it requires a decentralized validation mechanism that a blockchain provides. In this paper, we intend to make an exhaustive survey of various researches being carried out to secure IoT networks using blockchain technology. We also aim to provide a summarized view for various prospective research directions in IoT which can be addressed by blockchain technology.