An Overview of Blockchain Consensus Algorithms: Comparison, Challenges and Future Directions

Abstract

Like any other distributed system, the Blockchain technology relies on consensus algorithms in order to reach agreement and secure its network. Over the past few years, several kinds of consensus algorithms were created in the Blockchain ecosystem. In this paper, we present some main consensus algorithms used by the Blockchain technology. We also provide a comparison summary of their advantages and weaknesses as well as in which Blockchain type can be used. Furthermore, we present some challenges and possible directions related to the trendiest domains. With this work, for a given situation, we hope to help to choose the right algorithm to use. In addition, we hope to give directions to new possible algorithms propositions.