Research On Multi-copy Holding Audit Strategy Of Cloud Storage Dynamic Data

With the continuous development and further advancement of Chinese enterprises digitization and digital enterprises,a large amount of data is produced every day.How to effectively,safely and completely store massive data becomes the core problem in the field of information technology research.As a new service mode,cloud computing provides some effective technical solutions in mass data storage.More and more enterprises,organizations and individuals choose to store data in the cloud server.However,when users save data in the cloud,they lose direct control over the data,and the user data will be transformed from a trusted domain to an untrusted domain.The cloud service provider that stores the data can’t be trusted to delete data that users rarely access in order to get extra storage space.Cloud service providers may conceal user data loss caused by cloud storage server faults or hacker attacks.In addition,to save storage space,cloud service providers may reduce the number of data replicas and the consistency maintenance of replicas.Therefore,how to ensure data integrity and implement data holding audit in cloud storage has become an important topic of concern in the field of cloud security.In this context,auditing cloud data becomes an effective solution to verify the integrity of cloud data.This paper studies the key technologies of cloud computing data security audit,and on the basis of analyzing the existing data security audit,mainly aims at:(1)Aiming at the single copy holding audit problem of cloud storage dynamic data,a cloud storage data holding audit method based on algebraic signature and index matrix is proposed.By introducing a third party to outsource the audit task,algebraic signature is used to generate lightweight data labels,and the dynamic data holding verification is realized by combining index matrix.This includes the insertion,modification,and deletion of data blocks and data subblocks.The safety and feasibility of the proposed scheme are analyzed.The theoretical and experimental results show that the proposed strategy can effectively resist the attacker’s forgery spoofing,replay spoofing and substitution spoofing,and also reduce the computing and communication overhead.(2)Aiming at the problem of multi-copy data holding audit of cloud storage dynamic data,a multi-copy dynamic data holding audit scheme based on proxy re-signature is proposed.Random mask technology and bilinear pairing technology are introduced to generate ciphertext through symmetric encryption of the file to be uploaded,and a specified number of copies are generated by random mask processing of ciphertext.Generate auxiliary authentication information for each replica data block and data subblock stored on different servers to realize synchronous update of multiple replicas.Meanwhile,in the scheme,the proxy re-signer deals with encrypted data,avoiding the risk of data privacy disclosure.The scheme significantly reduces the computing cost of users and has certain practical application value.