Dual Data Possession Verification Scheme

The powerful computing and storage capabilities of cloud computing technology have enabled companies to access computers and storage systems in the cloud according to internal needs and switch resources to the appropriate applications.Cloud storage brings together a large number of different types of storage devices in the network to provide data storage and service access services.Users' data is stored in the cloud and users lose control of it.With the emergence of a series of information disclosure problems,data security in cloud storage is currently facing major challenges.The integrity of data in the cloud has become a concern.This dissertation mainly studies the integrity and credibility of data in cloud storage.The main tasks completed are as follows:(1)In order to realize the non-repudiation of data possession verification,this dissertation proposes a provable data possession scheme based on public verification and private verification.At the same time,it verifies the credibility of cloud service providers and users,and introduces COM functions.During the verification use the same metadata,simultaneously,and output the result pairs.Through the analysis of the result pairs,the credibility of cloud service providers and users can be determined.(2)In order to improve the speed of verification,this dissertation proposes a hierarchical data possession verification scheme for improvement of PPPDP method.When preprocessing files,the files are layered by accessing the granularity and number of detected files.Each layer of data is sampled and encrypted using a different authentication agent.The information returned by each agent to the third party is linked through the blockchain,and the integrity of the file is analyzed.This scheme can improve the verification speed and ensure the reliability of verification.