Analyzing Blockchain Consensus Mechanisms and their Applicability to Internet of Things Systems

Abstract

The consensus mechanism is the main component of blockchain technology, which allows multiple nodes to agree on a consistent view of data within the blockchain network. A carefully selected algorithm, on the basis of which a consensus of transactions occurs, can provide the network with such properties as fault tolerance and immutability. Currently, it is relevant to apply blockchain (with all its advantages) to Internet of Things (IoT) systems, which are gaining more and more popularity every year.  IoT systems are used in areas important to society such as healthcare, economics, agriculture, transport, and are also used in various forms of social security (smart cities, logistics, product tracking, parcels, etc.). Data integrity and consistency are extremely important in these areas, because hardware and software failure or discrediting the data may harm the company and its customers using IoT devices. In addition, the blockchain has become the basis for decentralized networks. The main difficulty of implementing blockchain in IoT is the lack of computing resources of these "smart devices". It follows from this that traditional consensus algorithms, for example, Proof of Work, are not applicable, as they are extremely resource-intensive. This article provides a comparative analysis of popular consensus mechanisms according to the list of developed criteria. Based on the results obtained, conclusions are drawn that help in choosing the most appropriate consensus mechanisms for applicability in IoT systems, and the conditions necessary for their integration are determined. The possibility of implementing both PoW and PoS algorithms in IoT systems using consensus algorithms specially developed for them, such as Microchain and Proof of Supply Chain Share, is also considered.