Research On Credibility Evaluation And Preservation Method Of Electronic Data Preservation

With the wide application of information technology and the continuous development of cyberspace,people's production and life related to cyberspace closely.As people's awareness of evidence have gradually increased,people begin to predictably preserve the electronic data that maybe lost in the future but maybe disputed.However,due to the fragility of electronic data and it's easy to delete or modified,it's difficult for parties to prove its authenticity when presenting digital evidence to the court.The third-party digital preservation platform provides electronic data preservation services with neutral status,it uses technical means to improve the probative force of electronic data and provide effective evidence support for the case once the dispute occurs.However,there are no legal norm or standard for the third-party digital preservation in current judiciary.There are differences in the technical capacity and the pattern of digital preservation among the third-party digital preservation platforms.Therefore,judges,lawyers and the parties urgently need an effective way to evaluate the credibility of electronic data of the third-party digital preservation.At the same time,the third-party digital preservation is in the stage of development,the digital preservation pattern needs further improvement.Regarding the issues above,this thesis focuses on the following aspects of the credibility of electronic data and digital preservation method:First of all,this thesis summarizes the existing patterns and the problems of the third-party digital preservation platforms.On this basis,from the perspectives of the need for judicial proof and the authenticity guarantee of electronic data,this thesis proposes a series of judging indicators and an evaluation method to measure the credibility of electronic data of the third-party digital preservation.It assists the judge and the party to assess and review the credibility of digital evidence under the third-party digital preservation scene.Secondly,this thesis designs a digital preservation method based on the practical Byzantine fault-tolerance algorithm.The method adopts the distributed evidence storage mode.Before the electronic data transmits,the original data is fixed through digital signature,timestamp and other technologies;Byzantine fault tolerance algorithm ensures the consistency and security of electronic data in the transmission and storage process.This method can guarantee the security and integrity of the electronic data in the process of digital preservation,also can effectively verify whether the data has been tampered,and realize the non-repudiation of the data subject.Finally,this thesis designs and implements a digital preservation system.The system consists of four modules: user identity management,data trusted fixed,data security storage,and preserved data verification.The feasibility of the scheme was verified by experiments,and the safety of the scheme was proved by theory.