Decentralized Online Crowdsourcing Mechanism Based On Blockchain Smart Contract

With the gradual promotion,crowdsourcing has become an efficient way to solve problems that are very complicated for computers and simple for human group intelligence in recent years.Due to the ability to make full use of external resources,significantly reduce the cost of value creation and improve efficiency,more and more enterprises in the computer and business sectors have chosen to freely and voluntarily crowdsource the services previously handled by employees to large non-specific group network.The traditional crowdsourcing model that is currently widely used is central based.Requesters with crowdsourcing needs publish tasks on crowdsourcing center servers or platforms,including task descriptions,requirements,and more.Workers who are interested in this task receive the task,process and submit the solution through the central server or platform.Finally,the central server or platform evaluates the workers'work and pays rewards according to certain rules.However,in the current situation,the mainstream crowdsourcing application adopts the offline auction mechanism,and this centralized mode currently faces various challenges such as high cost,single point of failure,and vulnerability to malicious attacks.These issues are worth studying and need to be addressed.The main work and contributions of this paper are as follows:Firstly,this paper analyzed the shortcomings of the offline static mechanism,pointed out that it cannot meet the current mainstream dynamic scenarios,and cannot deal with the problem of incentive compatibility in dynamic scenarios and has several challenges of centralization.This paper studied a dynamic crowdsourcing scenario,built a model and proposed a smart contract-based decentralized online crowdsourcing mechanism,which includes task assignment rules,reward payment rules and so on.The goal is to minimize the cost of outsourcing in a dynamic scenario where the future is uncertain,workers arrive randomly,while ensure that the workers can bid truthfully.Secondly,we learned and mastered the exclusive programming language Solidity of the blockchain smart contract Based on the mechanism of this paper,we designed and used the language to write the corresponding smart contract,which contains the main five functions to achieve the corresponding mechanism-Task publishing,worker quotation,task assignment,result presentation and reward payment.This enables the mechanism to be applied to Ethereum by leveraging the popular blockchain technology,to address the threat of centralization and to be able to truly run and process the actual data.Finally,we set up the experimental environment,deployed the smart contract in the private chain of Ethereum,and experimented by inputting a large amount of data.The results proved its effectiveness and we verified it's well performed by compared with off-line optimal.In this way,the entire crowdsourcing process under the mechanism no longer requires the participation of trusted third-party agencies,information and privacy security is guaranteed,and the cost is lower.