Research On Fair Exchange Mechanism Based On Blockchain

With the popularization of online services such as e-commerce and e-government,the need for fair exchange between two parties such as contract signing has arisen.In a dynamic and open Internet environment,the two parties often lack a trust foundation,which brings challenges to fair exchange.In the existing fair exchange solutions for Internet applications,the higher cost solutions based on trusted third parties are usually adopted.With the rapid development of blockchain technology,new ideas have been provided for the research of fair exchange protocols.Based on the analysis of existing fair exchange agreements,this paper studies and designs a blockchain-based fair trade scheme.The specific work is as follows:First,in view of the system performance bottlenecks and high costs caused by centralized processing in the traditional fair exchange scheme based on trusted third parties,a fair exchange scheme based on fuzzy signature is proposed.In the proposed scheme,the signature model uses concurrent signatures,and both parties of the exchange hold their own keystone,and the keystone are released through the blockchain transaction to bind their signatures.In the whole process,both parties to the exchange can complete the contract signing without the assistance of a centralized third party.On the basis of analyzing the security of the proposed scheme,the performance comparison with other similar schemes is further carried out,which shows that the scheme in this paper has higher computational efficiency.Secondly,considering that in some applications,the confidentiality of contract content transmission needs to be guaranteed at the same time,on the basis of the fair exchange scheme mentioned above,a fair exchange scheme based on signcryption is proposed.The scheme is based on verifiable encryption signature technology,and on the basis of ensuring the confidentiality and authentication of the transaction contract,the fairness of the contract transaction is realized.In addition,the use of a time lock mechanism further ensures the timeliness of transactions.The security proof under the random oracle model and the comparative analysis of simulation experiments show that the scheme proposed in this paper has good practicability.