RVC: A reputation and voting based blockchain consensus mechanism for edge computing-enabled IoT systems

By deploying edge servers around devices, edge computing brings computing resources far away from the cloud center close to the Internet of Things (IoT), which reduces latency and promotes the rapid development of IoT. Since edge servers and devices (hereafter referred to as NODEs) are highly scattered, blockchain is becoming one of the most promising solutions to enhance security issues for IoT. In the blockchain, a consensus mechanism determines how to achieve an agreement among nodes, hence it is an essential element for the operation and efficiency of the blockchain. However, due to the exponentially increasing of nodes in IoT, the consensus efficiency of the traditional consensus mechanism will be greatly reduced, and due to the lack of detection process for malicious nodes, its security will also reduce. To solve the above problems, in this paper, a Reputation and Voting based Consensus mechanism (RVC) is proposed. To reduce the time consumption of the consensus process, RVC adopts a reputation evaluation algorithm without complex hash calculations to select block proposers, which both consider the behaviors in edge computing and blockchain consensus. To prevent malicious nodes from participating in consensus, a filtering algorithm is designed for RVC, which can detect and filter nodes with malicious behaviors. Simulation results show that, RVC outperforms some traditional work. On time consumption, compared with AirBC and hybrid blockchain, RVC improved by 73.6% and 93.7% respectively. And on consensus security, RVC improved by 14% compared with LVBS. When the network scale and the proportion of malicious nodes change exponentially, RVC shows good scalability in terms of time consumption, successful consensus rate and transaction throughput.