Research On The Application Of Blockchain Technology In The Cash Flow System

Synchronization of cash flow and information flow is one of the core problems to be solved for clearing and payment between commercial banks and the People's Bank of China.This paper mainly studies the application of blockchain technology in cash flow,designs and implements a cash flow system based on blockchain by building a low-level alliance chain platform between the People's Bank of China and the commercial banks,utilizing the characteristics of decentralization and non-tampering of blockchain.The main work of this paper includes the following aspects:First,based on Hyperledger Fabric,an alliance platform for information sharing between the People's Bank of China and commercial banks is designed.The members of the alliance can record and query information credibly through intelligent contracts.The blockchain does not need centralized institutions,and can ensure the authenticity and traceability of data.Second,aiming at the privacy protection needs of participating institutions,this paper designs a privacy protection mechanism based on zero-knowledge proof of cash flow information.In the process of cash flow,the bundle right is used as the voucher of transaction,and the ownership verification and transfer of bundling right are realized by using public-private key encryption.Only commercial banks and the People's Bank of China,which are the parties involved in the transaction,as well as the supervisors,have the real key of data.While protecting the privacy of the participants,they also provide the technical means of confirmation and audit.Third,aiming at the storage problem of massive crown number text and picture data,a data storage scheme combining Hyperledger Fabric and InterPlanetary File System IPFS is designed.Firstly,we use MapFile-based file merging scheme to merge small crown number files;secondly,we store the merged files in IPFS and record their storage addresses in Hyperledger Fabric;finally,we generate a two-tier index structure of crown number records to facilitate information retrieval.When searching crown numbers,the merged files are retrieved according to the global index provided by MapFile,and then the crown numbers are located according to the two-dimensional index in the merged files.Forth,aiming at the query problem of massive crown numbers,we design a query scheme with HBase as the front end and data on the chain as the verification end.First,we query the record of crown numbers in HBase,and then query and verify the authenticity of the data in the blockchain according to the unique keywords queried.In the process of query,multi-dimensional index based on Hilbert space curve is used to realize fast query of crown number information.Last,A cash flow system based on blockchain technology is designed and implemented,including the functions of cash flow information storage,retrieval and bundle transfer.The experimental results show that,on the premise of protecting participants' privacy,this method achieves the basic functions of de-centralization,traceability,confirmation,multi-dimensional query and so on.