At present,the total amount of Io T data increases with the deployment of Io T sensors in different fields,and the collected Io T data often flows through sharing or transaction.In the process of flow,Io T data will go through a series of data processing,so it has become an urgent need for users to obtain data source and intermediate processing information to evaluate data quality.At present,Io T data provenance of has become a hot issue,through the Io T data provenance can be learned the source of Io T data,data processing and flow process information,and then help users judge whether the Io T data is true and reliable.However,the current data provenance implementation usually adopts the centralized way to store the provenance information,which is prone to the problems of fake users and malicious attackers,such as malicious falsification,tampering and single point of failure,so that the security and integrity of the provenance information are threatened.Blockchain has attracted the attention of various industries due to its decentralized,completely distributed and tamper-proof features,which can provide technical support for Io T data provenance.Therefore,the data provenance information management and key mechanism of the Io T will be studied based on the Blockchain in this paper,and the specific research content is as follows:First,research on the data traceability model of Io T based on PROV.The data traceability process of the Io T is analyzed to extract the provenance information.Then,the data traceability model of Io T is established based on PROV,which extends the traceability vocabulary in the data flow process of the Io T.At the same time,an instance scenario of the data flow of the Io T is taken as an example,and the basic concepts in the model are described and expressed based on this scenario.Second,research on the model and key mechanism of data provenance system of Io T based on Blockchain.Aiming at the problems of malicious tampering and fraud caused by the current centralized storage model of provenance information,a hierarchical design of Io T data traceability was proposed by combining the Blockchain and the Io T data provenance model based PROV,and the contents of each layer and specific implementation methods were elaborated.In view of the problem that nonparticipants fake identity in the current Io T data flow process and lead to untrustworthy provenance information,an identity credibility authentication scheme is proposed,which can verify the detailed identity of each participant in the data flow process.In terms of the storage and query of provenance information based on Blockchain,in order to ensure the safe storage and efficient query of the provenance information in the Io T data traceability,combined with the Io T data traceability method and the characteristics of information storage based on Blockchain,this paper proposes the provenance information storage and query mechanism based on the Blockchain.Third,the design and implementation of the data traceability prototype system of Io T based on Ethereum.This paper implements a traceability prototype system based on Io T data service platform based on Ethereum,intelligent contract,Web development framework and other technologies.The prototype system realizes the overall architecture based on the hierarchical design of Io T data traceability,and implements each module according to the function division and key mechanism of each level.It realizes the functions of authentication scheme based on Blockchain,collection of provenance information and security management of provenance information.Finally,the function of the prototype system is tested under the actual Io T data flow scenario.The test results show that the prototype system can realize the safe storage and effective query of provenance information. |