BECHAIN: A Sharding Blockchain With Higher Security

Xiaochang Guo, Gang Liu, Haoyan Ling, Lei Meng, Tao Wang

Abstract: Sharding technology achieves parallel processing of transactions by dividing the network into multiple independent parts, namely shards, significantly increasing the throughput of the blockchain system and reducing transaction processing latency, thereby improving its scalability. Although sharding technology enhances blockchain performance, it also introduces new security challenges, as an individual shard is more vulnerable to attacks compared to the entire network, potentially compromising its consensus reliability. To address these challenges, we propose BECHAIN: a sharding blockchain system with excellent Byzantine node tolerance. It incorporates a series of effective security measures, such as improved node allocation methods, enhanced inter-shard collaborative defense mechanisms, and refined malicious node monitoring strategies, to bolster the blockchain system’s defense against malicious nodes. Key measures include random node allocation, a node reputation scoring model, consensus supervision chain, and shard reconfiguration. Simulation results show that BECHAIN achieves linear scalability and enhances system security by increasing the consensus success rate.