Research And Design Of Blockchain Consensus Algorithm For Secure Expansio

Blockchain systems ensure data integrity and immutability in decentralized and untrusted environments,and these characteristics depend on the distributed consensus algorithms used by the blockchain.However,traditional blockchain consensus algorithms have certain security and efficiency issues,and the scalability of the blockchain restricts the large-scale application of blockchain systems.Therefore,this paper focuses on the security issues of consensus algorithms and the scalability issues of the blockchain,with the following specific work:(1)The PoW consensus algorithm has been proved to be incentive incompatible,existing computing centralization under high reward differences and slow convergence of forks in extreme cases.Based on this,an incentive-compatible-based consensus algorithm SSPoW is proposed.By introducing local solutions to calculate the computing power aggregated on the block chain,the explicit quantification of computing power is used to speed up the convergence of the fork,thus satisfying the consistency of the blockchain.Incentive compatibility is achieved by improving the reward scheme,which reduces the problem of computing centralization caused by high reward differences.Simulation results prove that the proposed algorithm can effectively reduce the reward differences and is more efficient than the traditional PoW consensus algorithm,which has positive implications for improving system security and consensus efficiency.(2)Sharding technology is considered as the key to solve the blockchain scalability problem,but suffers from intra-shard consensus security problem and data consistency problem.Based on this,a blockchain sharding model based on star architecture is proposed.A global mining algorithm is used to increase the computational power of a single shard,which increases the attack cost of adversaries and achieves the goal of intra-shard consensus security.Meanwhile,a sliding window algorithm is designed to securely confirm the global order of blocks on all parallel chains,thus achieving blockchain data consistency.Simulation results demonstrate that the proposed sharding model outperforms the existing Omni Ledger sharding scheme in terms of throughput,transaction confirmation delay and data consistency.