An Improved Practical Byzantine Fault Tolerance Algorithm Based on Vague Sets and Random Numbers

Aiming at the problems of improper election of master nodes of the improved PBFT algorithm and the tendency of system centralization, an improved PBFT consensus algorithm based on vague sets and random numbers is proposed in this paper. First of all, vague sets are used not only considering the promotion effect brought by the positive vote to the node, but also considering the bad impact of the negative vote on the node, which can distinguish the reputation value of the node better. Then, we simplify the consistency protocol of the PBFT, this can reduce the complexity of communication. Finally, the master node is determined by the random number generation based on Proof of Vote (PoV). The random number is established with the signature and timestamp of the node, which increases the unpredictability of the master node number and ensures the security of the system. Through experiments on systems of different sizes, it is proved that the accuracy of distinguishing node reputation values is improved by 8% compared with the previous algorithms. It can also ensure that the nodes in all consensus node sets have the same probability of becoming master nodes.