Research On Real-Time Blockchain Difficulty Adjustment Scheme And Computing Power Recovery Scheme Based On Proof-of-Work Mechanism

Blockchain is an open,transparent and tamper-resistant decentralized public digital ledger technology,which is widely used in many fields such as cryptocurrency,times-tamp proof,and evidence retention.As the most stable and widely used blockchain con-sensus algorithm,the proof-of-work consensus algorithm has successfully maintained the average block time of many blockchain applications such as Bitcoin at design value for a long time.However,due to the increasingly popular application of blockchain led by cryptocurrency in recent years,the market value has fluctuated significantly,and more and more miners have joined the blockchain mining network.Every join or exit operation of miners directly affects the computing power of the entire network.Today's difficulty adjustment algorithms often have poor real-time performance and are unable to respond to such violent fluctuations in the computing power of the entire network in a timely manner,resulting in a significantly longer block time.For the blockchain sys-tem,the stability of the block time directly affects the stability of its services.Another serious problem that restricts the development of blockchain is that the calculations used by miners when mining with proof-of-work have no real value,and blockchain mining is a huge waste of power resources.These two problems greatly restrict the further development of blockchain applications.This paper aims to solve the above two key problems restricting the development of blockchain.In view of the real-time problem of blockchain proof-of-work consensus difficulty update and the waste of computing power in mining calculations,we will research and improve the blockchain scheme.The main research contents of this paper are as follows:1.In view of the real-time problem of blockchain proof-of-work consensus diffi-culty update,we proposed a real-time emphasis based on weak proof-of-work,that is,a difficulty adjustment algorithm that is highly sensitive to changes in the computing power of the entire network.The consensus mechanism of this real-time difficulty ad-justment algorithm is named RTPo W(Real-Time Proof-of-Work).In this scheme,the blockchain system enables miners to actively submit weak block headers in the mining process to more accurately estimate the real-time computing power of the entire net-work through the rate generated by the weak block headers,and obtain more real-time computing power through the calculation results to get strong real-time difficulty tar-get.Testing and simulation proved that the real-time difficulty adjustment algorithm can make the block generation speed to maintain the same stability as the constant com-puting power environment even when the computing power fluctuates violently.In ad-dition,this paper discusses the potential attack possibilities of the scheme,and proposes resistance algorithms or solutions to patch these vulnerabilities.2.In view of the difficulty of simulating experiments under a single host for a dis-tributed system of blockchain,this paper proposes two blockchain testing frameworks to support the experiments and simulations of the above schemes.Aiming at the re-search on the consensus process of the blockchain,this paper proposes a blockchain consensus simulation scheme based on the mininet virtual network topology simulation technology.For the research on the block generation time of the blockchain system,this paper simulates the network communication in a stand-alone environment.As well as the simplified abstraction of mining,a blockchain simulation scheme based on time slice polling is proposed,and a distributed blockchain system with high hashing power is implemented virtually in a low-power simulation environment based on it.In order to facilitate testing,this paper designs a blockchain experiment platform based on Flask and Materialize Css.Echart is used in the front-end to visualize the experimental results in real time,and the matplotlib library is used to implement the visualization and export of the test results.3.In view of the waste of computing power in the proof-of-work,this paper pro-poses hash-with-workloads,and based on this,a blockchain outsourcing computing platform that is anti-collision,open and transparent is designed.In this scheme,by transforming the hash algorithm structure in the proof of work and inserting a useful workload to it,this paper implements the hash-with-workloads function.This paper implements a blockchain outsourcing computing platform based on blockchain,asym-metric encryption and magnetic link distributed download technology and prevents the potential cheating possibility of payload hashing.The blockchain outsourced comput-ing platform and the hash-with-workloads function together constitute a general con-sensus computing power recovery scheme for proof-of-work.In order to test the com-puting power recovery rate of the computing power recovery scheme,this paper selects the large matrix calculation as the workload in the test,improves the algorithm design,and finally achieves a computing power recovery rate of 50% in the experiment.