Auditable Protocols For Fair Payment And Physical Asset Delivery Based On Smart Contracts

With the rapid development of electronic information technology,online transaction will gradually surpass traditional market transaction,among which online payment and asset delivery become the focus of attention.But in fact,due to the incomplete third-party payment mechanism and the intrusion risk of various charging Trojan,it is easy to cause a trust crisis.The existing centralized framework often leads to information asymmetry between the two sides of the transaction,and the auditing problem in the process of commodity transportation is also unidirectional.Therefore,how to realize the fairness of payment and the auditability of assets in the distributed system is a challenging problem.In addition,in order to obtain effective reputation evaluation,we need to design a reliably distributed reputation system for privacy protection.The emerging blockchain technology provides a new method with its openness,transparency and verifiability.This paper uses block chain technology to design auditable protocols for fair payment and asset delivery in e-commerce,as well as reputation system in decentralized environment.The main results are as follows:We propose an auditable fair payment and physical asset delivery protocol based on smart contracts.Three types of smart contracts are designed to achieve reliable and fair payment among merchants,consumers and logistics companies.The traceability and auditability of blockchain provide an effective method to audit assets and data sharing in the whole transportation.In view of the phenomenon of goods being switched,the way of"pre-verification" is added.In order to prevent the illegal elements to fake pickup code,induce consumers to conduct illegal operations,cause property loss,in our system the pickup codes are generated by consumers to reduce the risk of fraud.In addition,our plan designs a complete return process for the first time,providing better service experience and higher efficiency for consumers.Finally,all the contracts involved in the scheme are implemented and deployed on the ethereum test network.The results of security analysis and evaluation showed that our scheme was improved in cost,with high security and availability.We propose a privacy protection reputation scheme in a decentralized environment.To ensure that consumers are able to obtain true evaluation value and share their evaluation information securely without compromising their privacy.Two types of contracts are mainly designed,which are respectively used to obtain evaluation value from consumers and publicly store reputation score.The non-tampering feature of blockchain guarantees the authenticity of evaluation value.The ring signature technology is used to protect the evaluator’s private data,and a complete reputation calculation parameter is designed,And designed a complete reputation calculation parameters,based on the time evaluation principle,from far to near evaluation value to set the weight.Reduce the impact on existing values and avoid manipulation of existing market data.