State of the art and challenges facing consensus protocols on blockchain

Nowadays, the blockchain is a favorite platform, for instance, for use with cryptocurrency, smart contracts, IoT, and so forth. Blockchains are distributed ledgers that enable parties who do not trust each other to maintain states. The parties agree on the existence, values, and histories of the states. The blockchain applies the consensus protocol to verify the block which is distributing the network node. Consensus has many practices such as, for example, Byzantine general problem, Proof of work, and Proof of stake. However, there have not been numerous papers that have undertaken analysis with regard to various aspects, and which have incorporated the adoption summary as appropriate to the application. In this paper, we have provided a technical verification review with regard to the consensus algorithm taken from previous research. The audience will receive a consensus protocol, and the algorithm typically analyzes the application to match which platform is appropriate by viewing the node identity, energy saving and the tolerated power of the adversary, the data model, language, execution, application, and examples. Finally, we finish by presenting several research directions with regard to the consensus protocol.