| Since blockchain technology came out,it has received the most extensive attention.Its most representative and successful application is bitcoin proposed by Nakamoto in2008.With the advantages of decentralization,distrust,collective maintenance,security and non tamperability,blockchain has been gradually applied to finance,anti-counterfeiting,supply chain system,data traceability and other fields.At present,most researches on the security of blockchain focus on the variants of attack methods,and how to defend against attacks is relatively small.Therefore,the research on the security of blockchain mining pools in this article is of great significance.In the early days of bitcoin development,the mining difficulty was relatively low,so the user made the computer CPU to participate in mining.With the development of bitcoin,more and more people are involved in mining and the difficulty of mining is increasing.The mining nodes are concentrated together to form a mining pool.For the miners,if they choose the mining pool,it becomes the primary problem.Therefore,the research on mine pool selection strategy in this paper can give miners reference value..This paper studies the strategy of ore pool selection.In the blockchain network based on proof of work(Po W),miners usually choose to join the ore pool.Because there are multiple mining pools in the current blockchain network,different mining pools have different computing power and adopt different reward distribution systems,miners can get different benefits from different mining pools.Generally,there are three reward distribution systems used in mining pools,namely,promotional,pay per share and pay per last n-share.Aiming at the problem of mine pool selection faced by miners,a model of mine pool selection based on risk decision-making criteria is established,and the influence of pool calculation power and reward mechanism on the optimal selection strategy of miners is studied.Firstly,the income of miners in different ore pools is calculated,and the income matrix is given.Secondly,the optimal selection strategy is obtained based on the maximum possibility criterion and the expectation criterion respectively,and the influence of N on the selection strategy of ore pools is studied.Finally,through the simulation experiment,the proposed strategy is verified and analyzed.The experimental results show that compared with the simple strategy,the proposed strategy can bring more benefits to the miners in most cases.This paper studies the security technology of blockchain.Block interception attack is a typical attack mode in blockchain.It enters the ore pool through computational power penetration and only sends part of the workload certificate to the manager of the ore pool.The complete workload is discarded and the profits of the ore pool are shared.In order to solve this problem,this paper first summarizes the typical attacks of blockchain,analyzes the block interception attack principle and its impact on the mining pool in detail,and summarizes and discusses the current research status of defense methods to deal with the block interception attack.In order to improve the safety of the mine pool,the miner who submits the full workload proof is rewarded to reduce the expected income of the attacker,so as to reduce his desire to attack and ensure the safety of the mine pool.Finally,the relationship between the size of the special reward and whether he can obtain the additional income when launching the attack is quantitatively analyzed through experiments. |
