ETH 2.0 State Sharding Anti-collusion Attack Scheme Design Using Multi-round Verification

Blockchain technology is the key technology to realize distributed bookkeeping.With its decentralized advantages and the support of cryptography,blockchain technology has challenged the traditional trust system,it has changed the way of value sharing,and has promoted the transformation of information Internet into value Internet.However,with the rapid development of blockchain technology,the scalability problem has become serious.To solve this problem,developers have proposed a variety of expansion solutions such as sharding,DAG,state channel,side chain,etc.Compared with multiple on-chain capacity expansion solutions,sharding is the most promising capacity expansion solution without reducing the degree of decentralization.But because it is still in its infancy and exploration stage,there are still some problems,such as the state sharding proposed by Ethereum 2.0,which trying to avoid the problem of collusion attacks,although setting the nodes in the shard to a higher value,to a certain extent Reduced the probability of collusion attacks,but this also greatly sacrificed the performance of the system.Once the number of verification nodes in the shard decreases,the probability of collusion attacks will increase and the system security will be threatened.In view of the collusion attack problem in the above Ethereum 2.0 state sharding scheme,the paper proposes a multi-round verification scheme against collusion attacks in state sharding.The core idea of the multi-round verification scheme is to perform multiple rounds of consensus verification on the same transaction in the shard,to ensure that the number of verification results reached agreement is equal to two,while reducing the probability of collusion attacks,improve system performance.At the same time,the node random allocation algorithm is selected to ensure that each round of node allocation guarantees a high randomness and unpredictability to ensure the safety of the system.This paper conducts simulation experiments on the proposed improved scheme in a laboratory simulation environment,and conducts comparative experiments on the three aspects of transaction verification rate,average block generation time,and transaction processing capability.The experimental results show that the multi-round verification scheme effectively improves the system performance while effectively reducing the probability of collusion attacks.During each round of node redistribution,a high randomness and unpredictability are ensured,and the security of the system is guaranteed.