Design And Implementation Of A Supply Chain Platform Based On The Relay Chain Mechanism For Heterogeneous Blockchain Scenario

In the cross-border seafood supply chain scenario,products go through multiple circulation steps and organizations from their origin to table.On the one hand,there are problems with traditional seafood supply chain such as data fraud,low transparency,and difficulty in tracking.On the other hand,the heterogeneity of various organiza-tions' systems makes it impossible to exchange data and complement functions,result-ing in isolated value islands.Blockchain technology is characterized with decentraliza-tion,non-tampering,and traceability,which can ensure the transparency and traceabil-ity of supply chain business data.As an important way to realize blockchain's interop-erability,cross-chain technology breaks the barriers between heterogeneous blockchain systems and establishes a bridge for data exchange and value circulation.This thesis designs and implements a cross-border seafood supply chain platform based on blockchain and cross-chain technology.The platform includes a data oper-ation module,a cross-chain data traceability module,and a smart contract manage-ment module.Among them,the data operation module provides business data stor-age,query,update,and deletion functions.The cross-chain data traceability module provides cross-chain data exchange functions between homogeneous or heterogeneous blockchain systems.The smart contract management module provides contract deploy-ment,upgrade,registration and audit functions.The platform is divided into three layers: front end,service layer,and network layer.The network layer provides underlying ledger services and cross-chain services.This platform uses the mainstream consortium blockchain technology - Hyperledger Fabric and Ethereum as the underlying blockchain network.Hyperledger Fabric chain-code is implemented in Go language and deployed in a Docker container.Ethereum smart contracts are implemented in Solidity language and loaded by the Ethereum Vir-tual Machine(EVM).In order to solve the interoperability problem between heteroge-neous blockchain systems,a cross-chain platform was built.The cross-chain platform includes a relay chain Bit XHub,two Hyperledger Fabric cross-chain gateways,and an Ethereum cross-chain gateway.The service layer is designed as an independent middle layer,which encapsulates the common operations of Hyperledger Fabric and provides the interfaces for the front end.This layer uses the Gin framework to encapsulate the application chain SDK and uses the Go language to implement business processing logics.The service layer can be upgraded independently without affecting the front end,which improves the stability of the business system.The platform uses HTML,CSS,and Java Script technology to build a front end,provides users with a good human-computer interaction interface,and improves the usability of the platform.During the development process,this thesis uses the tool Postman to simulate front-end requests and conducted module tests on the platform.Once the development is completed,this thesis carries out integration testing and performance testing.The test results show that the supply chain platform based on the relay chain mechanism realizes functions such as business data operation,cross-chain data traceability,and smart contract management.The performance test uses the open source tool Premo.The results show that the platform can process up to 937 transactions per second(TPS)under the condition of normal operation,which can meet the business needs in real sce-narios.This thesis can be valuable effort and exploration of blockchain and cross-chain technology in cross-border supply chain scenarios,and provides a reference platform for cross-chain researchers and practitioners.