Research On Blockchain Sharding Method Based On Asynchronous Consensus

The application of blockchain technology is faced with problems and challenges such as higher hardware requirements,lower throughput of blockchain system,many loopholes in consensus mechanism,poor transaction information processing effect.This paper conducts relevant research on the block chain fragmentation method based on asynchronous consensus.In order to better deal with the bottleneck problem of blockchain system,this paper studies from three aspects: the blockchain sharding technology,consensus mechanism and cross-shard transaction.The main contributions of this paper are summarized as follows:(1)In order to overcome the poor blockchain sharding effect and uneven distribution of nodes,a matrix-based jumping hash sharding algorithm is proposed.On the basis of efficient consistent hash algorithm,a combination of node credit strategy and virtual sharding technology is used to construct blockchain sharding,and the uniformity of node distribution is verified according to node migration.Experimental results show that the proposed algorithm reduces shard construction time24.7% faster than Ethereum project,and 18.3% faster than Zilliqa project.(2)In order to solve the low consensus efficiency of blockchain sharding system,on the basis of sharding technology,we design a aynchronous consensus by the bottom asynchronous and upper asynchronous consensus groups to build the layered architecture,and the mixed consensus algorithm DB-PBFT is proposed(based on borda count of Delegated Proof of Stake and Practical Byzantine Fault Tolerance algorithm).The realization of asynchronous consensus process of asynchronous consensus node election,node block out,node verification and malicious node processing,which can better adapt to the asynchronous environment without sacrificing the security of the blockchain system too much.Experimental results show that the proposed hybrid consensus algorithm under asynchronous consensus architecture improves consensus efficiency and reduces consensus time by 30.5% compared with the practical Byzantine fault-tolerant algorithm alone.(3)In order to deal with the low performance of transaction verification of blockchain sharding system,a cross-sharding transaction strategy of blockchain sharding system is proposed.On the basis of asynchronous consensus architecture,multi-shard and multi-consensus verification methods are used for transaction verification.The cross-shard transaction model of blockchain realizes cross-shard transaction strategy through shard transaction algorithm and transaction process.Experimental results show that the proposed cross-shard transaction delay is 50% faster than Ethereum and 35% faster than Zilliqa,and the throughput growth rate is 5 times and 0.4 times higher than those of Ethereum and Zilliqa respectively without affecting data consistency.