An Optimization Model for Transaction Placement in Blockchain Shards

Abstract Sharding technology can be used to improve the scalability of a blockchain system. The suitable placement of transactions into shards can reduce cross-shard ones, so as to improve system throughput and reduce delay. An optimization model for transaction placement to blockchain shards is proposed. Based on time analysis and a transaction flow graph, the fitness is computed to decide which shard is the most suitable one to place a transaction. The experimental results show that the proposed model can effectively reduce cross-shard transactions and reduce transaction delay.