Mosaic - A Blockchain Consensus Algorithm Based on Random Number Generation

Consensus algorithms can be considered as the core of blockchain technology. Different algorithms provide various advantages and disadvantages to the platform, which can cause the variation in the aspects of scalability, reliability, security, and performance. Deploying a blockchain platform with a consensus algorithm that is not suitable for the situated scenario may lead to low efficiency, waste of energy, unfairness and more. As more businesses are trying to introduce blockchain into their system, there is a demand for selecting consensus algorithms that are suitable for a private chain. Most of the current consensus algorithms are Voting-based or PBFT-based. However, Voting-based algorithms may suffer much from leader-crash, while PBFT-based algorithms may experience network congestion when implemented in a huge network due to its broadcast-like confirmation steps. In this paper, we aim to propose a new type of consensus algorithm based solely on Random Number Generation, called Mosaic. The selection is not only due to its low computational cost compared to cryptographically proof-based algorithms, but also because of its acceptable unpredictability that makes the election fairer. In the evaluation, we demonstrate that Mosaic is more efficient than PBFT-based schemes in large-scale while also providing fault tolerance compared to Raft.