Securing multi-chain consensus against diverse miner behavior attacks in blockchain networks

As cross-chain technologies enable interactions among different blockchains (hereinafter “chains”), multi-chain consensus is becoming increasingly important in blockchain networks. However, more attention has been paid to single-chain consensus schemes. Multi-chain consensus schemes with trusted miner participation have not been considered, thus offering opportunities for malicious users to launch diverse miner behavior (DMB) attacks on different chains. DMB attackers can be friendly in the consensus process on some chains, called mask chains, to enhance their trust value, while on others, called kill chains, they engage in destructive behaviors on the network. In this paper, we propose a multi-chain consensus scheme named Proof-of-DiscTrust (PoDT) to defend against DMB attacks. The idea of distinctive trust (DiscTrust) is introduced to evaluate the trust value of each user across different chains. The trustworthiness of a user is split into local and global trust values. A dynamic behavior prediction scheme is designed to enforce DiscTrust to prevent an intensive DMB attacker from maintaining strong trust by alternately creating true or false blocks on the kill chain. Three trusted miner selection algorithms for multi-chain environments can be implemented to select network miners, chain miners, and chain miner leaders, separately. Simulation results show that PoDT is secure against DMB attacks and more effective than traditional consensus schemes in multi-chain environments.