Research On Security Mechanism Of Cloud Storage In Digital Campus

With the rapid development of digital campus, the amount of files and the visits to files increase sharply, distributed cloud storage system replace traditional file system to an increasing extent. Distributed cloud storage system can effectively solve the storage of large-volume, big directory and mass small files in digital campus. Networked storage pattern should cater to mass data storage, but in the meantime, it caused many secured problems. The secured problems of reliability confidentiality and integrity of data storage become the new challenge of distributed cloud storage system in digital campus.According to the current situation of the file storage and the new challenge of digital campus, based on the research about techniques and implementations of existing distributed cloud stotage systems, this paper designed a metadata and data separated architecture for secured data storage named MeSe, and for the secured storage problem, designed and implemented secured mechanisms for mass file storage.This main work done in this paper includes the following items:1. Desigend and implemented a metadata and data separated architecture for secured storage-MeSe architecture. In MeSe architecture, the metadata server is placed alone in front of mass cloud storage system. And it’s conducive to control independently, improved the security of MeSe architecture. Meanwile, based on threat modeling methodology and distributed cloud storage system, presented a formal threat modeling method. On this basis, we use this threat modeling method to do detailed analysis of MeSe architecture2. Designed and implemented a sensitive data fragment and encoding mechanism based on security classification for MeSe architecture. It puts the data fragments into the mass cloud storage system distributively to keep the reliability confidentiality and integrity of data. On this basis, this paper designed a file incremental update policy which has low network transmission overhead and based on sensitive data fragment and encoding mechanism. This policy only transmits the modificated data fragments in file accessing and updating to minimize network transmission overhead.3. In order to implement the secured data sharing among systems in digital campus and based on MeSe architecture, this paper designed a metadata secured sharing mechanism based on authentication and authorization technologies. This mechanism can make sure the data and user informations will not be divulged during the data shring.