A Novel Semifragile Consensus Algorithm Based on Credit Space for Consortium Blockchain

Abstract

Nowadays, blockchain is known as a new generation of secure information technologies for realizing business and industrial sustainability, and consensus algorithm is the key technology of blockchain. In order to solve the problem of “oligarchy” nodes and excessive punishment for nodes in existing credit consensus algorithms, a novel semifragile consensus algorithm based on the credit space for consortium blockchain is proposed in this paper. Firstly, the accounting node selection mechanism based on credit space is proposed. The credit value of the node is calculated according to a novel credit evaluation model, and then the credit space of the node is allocated according to the size of the credit value. Afterward, a random algorithm is used to select the accounting node in the credit space. This mechanism effectively inhibits the generation of “oligarchy” nodes and maintains the enthusiasm of nodes. Secondly, this paper proposes a semifragile hierarchical punishment mechanism, which punishes the malicious nodes with severe measures and gives the nonmalicious nodes the opportunity to continue participating in the consensus. So, this semifragile punishment mechanism solves the problem of excessive punishment of nodes. Experimental simulation results demonstrate that the proposed consensus algorithm has randomness while maintaining the credit incentive among nodes. In addition, the node’s punishment mechanism is more reasonable. This algorithm has better security and can be well applied to consortium blockchain scenarios.