I. Introduction

II. Protocol Overview and Preliminaries

III. Distributed Consensus Mechanisms Based on Proof of Concepts

IV. Strategies of Rational Nodes in the Framework of Nakamoto Consensus Protocols

V. Virtual Block Mining and Hybrid Consensus Mechanisms Beyond Proof of Concepts

VI. Relaxed and Parallel Consensus Protocols for Performance Scalability

VII. Emerging Applications and Research Issues of Blockchains with Public Consensus

VIII. Conclusions