Research On Key Technologies Of Blockchain Trustworthy Storage For Heterogeneous Data From Outside Chain Systems

The popularity of big data applications on the Internet has made data sharing and data replication among heterogeneous distributed systems very frequent,and ensuring the integrity and consistency of data among large-scale distributed heterogeneous systems is the core key technology in the era of big data.Blockchain technology presents features such as distributed,openness,and non-tamperable information to provide secure and verifiable technical support for distributed heterogeneous data consistency management.However,the extension of blockchain security to various off-chain distributed heterogeneous application systems on the Internet still faces many challenges:①The non-adaptation problem of off-chain systems and blockchain security verification protocols.The network protocols of various off-chain systems are independent and perfect,and these protocols themselves do not support blockchain-based proofs and lack interfaces to interact with blockchain,so it is difficult to unify inside and outside the chain into a whole;② the distributed storage system under the chain lacks hard guarantee of availability.The off-chain system has been running for a long time and the historical data is huge,which will consume a lot of space when deposited on the chain.If you choose to use offchain storage to extend the storage of the blockchain,the off-chain system is not controlled by the blockchain and there is still a possibility of data loss;③ the contradiction between the frequent exchange of data inside and outside the chain and the isolation of data inside the chain.Blockchain is a closed system,and in order to ensure the security of data it needs to be isolated from the outside world,while this paper requires data to enter and leave the chain frequently,which is a big challenge for the security of blockchain itself.For the problem of using blockchain to provide secure verification and storage for offchain data,we summarize the existing research applications and propose a new solution based on it.Using the methodological ideas of analysis and synthesis,we divide the problem into several aspects to solve it one by one,and propose the use of prophecy machine to communicate inside and outside the chain,and use the off-chain distributed system storage with availability guarantee to store and verify the content of off-chain data.The method system includes:①for the problem of non-adaptation of off-chain system and blockchain security verification protocol,the overall architecture method to support off-chain heterogeneous system is proposed,and the architecture supports the adjustment of off-chain data processing,generates necessary mappings,designs data come in and go out process,provides detailed description for off-chain data storage and verification,and overcomes the problem of how to use blockchain for other heterogeneous system data;② To address the problem of lack of hard guarantee of availability of distributed storage system under the chain,we propose the method of receiving off-chain data based on the off-chain IPFS system with parallelizable storage reputation consensus,which firstly improves the scalability of blockchain storage,and the method uses reputation mechanism to select trusted nodes and parallelizable storage layer consensus,which not only ensures storage availability but also allows simultaneous storage of multiple files.This solves a series of problems in blockchain storage performance;③ For the contradiction between the frequent exchange of data inside and outside the chain and the isolation of data inside the chain,the method of interaction inside and outside the chain based on distributed bidirectional oracle is proposed,and the method improves the current oracle so that it can transmit data in two directions and configures the corresponding off-chain components in each off-chain node to distribute the processing of oracles,and through PBFT consensus further ensures the reliability of oracles and solves the problem of frequent interactions inside and outside the chain.In this paper,we construct an experimental system based on Ethernet,and use the dataset publicly provided by NETWORK REPOSITORY to verify the method of data storage and verification proposed in the article,and prove the effectiveness of this system.The reputation mechanism proposed in the article performs well in terms of fairness and rationality,and the results meet the expected requirements,effectively assisting the selection of trusted nodes and achieving more secure storage.Meanwhile,the parallelizable storage layer consensus proposed in the article makes acceptable in terms of time efficiency,and has a good balance between security and efficiency.For the distributed bidirectional oracle proposed in this paper,the storage cost is analyzed.The time spent on file storage,file retrieval,and file update is experimentally tested,which shows that when the file is at a certain size,it can have high change efficiency,but the time overhead is inevitably increased due to the use of hash processing files.The experiments also test the on-chain storage overhead and conclude that using this paper’s scheme can effectively reduce on-chain storage in the case of stored file update rate highland.These provide a scientific basis and application validation for the future integration of the advantages of blockchain with off-chain systems such as the Internet and integrated applications.