RROGE: A Reputation and Risk-Based Off-Chain Group Execution Scheme for Smart Contracts

Abstract

Off-chain execution schemes are a promising solution for enhancing block-chain scalability, reducing on-chain resource consumption, transaction costs, and processing time while improving data privacy. Nevertheless, off-chain execution schemes typically run smart contracts within small-scale execution groups. Since the number of nodes required to reach consensus is small, it is more likely that malicious nodes will gather in one execution group, causing the execution group to be controlled. We propose a reputation and risk-based off-chain group execution scheme for smart contracts. The scheme distributes potential malicious nodes across different execution groups, preventing any group from being dominated by malicious nodes. By integrating trust management mechanisms and a genetic algorithm, the proposed scheme mitigates the risk of malicious nodes colluding in a single group. This approach minimizes the likelihood of malicious node collusion and enhances the credibility of the execution group. Experiments demonstrate that the proposed scheme enhances blockchain throughput while increasing resilience against malicious attacks.