Research On The Integrity Audit Mechanism Of Data Dynamic Update In Cloud Environment

Behind the widespread application of cloud computing services,the support of massive data storage technology is required.In the massive data cloud storage service,some cloud service providers do not store data in accordance with the service level agreement,which may conceal data loss from users,or directly Some infrequent or never accessed data is discarded,which exposes user data to great risks.Therefore,integrity auditing of data has become a key issue that promotes the continuous development of cloud storage services.The earliest Provable Data Possession(PDP)mechanism only completes static audits.Although the improved audit program extends the dynamic audit function,it will generate a lot of auxiliary information and storage overhead.Therefore,the establishment of an efficient data dynamic update integrity audit mechanism can improve the storage security of cloud data.Based on the authentication data structure and the BLS signature algorithm,this paper proposes an audit mechanism that supports the dynamic update of data integrity.It simplifies the update process by constructing a dense hash tree(Dense Hash Tree,DHT),and uses homomorphic verification tag technology to avoid direct participation of data entities.Integrity verification calculation,and the backbone server in the cloud service provider(Cloud Service Provider,CSP)aggregates multiple message signatures to reduce the number of challenge-response interactions and achieve the purpose of reducing communication overhead.As DHT can store more data files than Merkle hash trees,there are still more auxiliary authentication information and greater waste of system resources when faced with large-scale data storage,and it is difficult to achieve the expected audit effect.In view of this,this research further improves the DHT integrity verification algorithm.By setting a local root node,the overall authentication is changed to partial authentication,so that TPAdoes not need to reconstruct the DHT,but only needs to modify the data structure of the partial authentication subtree.Complete the proof of completeness of data dynamic update.The improved data integrity audit mechanism has significantly improved the accuracy of audit results and audit efficiency.On the other hand,the adversary’s forgery attacks and replay attacks during the audit process will also threaten the information security of cloud users,leading to the leakage and destruction of users’ stored data files,and malicious CSPs will not only conceal the fact that data has been damaged,And some CSPs may collude with TPA to forge data signatures in an attempt to use false evidence to obtain commercial benefits through audit verification.In view of this,this research uses the irreversibility of the hash function to increase the difficulty of cracking by the malicious adversary by building adversary games for security analysis,reducing the risk of data information being stolen during the information communication process,and further enhancing the inter-cloud storage environment Security under audit.Experimental analysis shows that the data integrity audit mechanism based on DHT and BLS proposed in this paper can effectively reduce the time overhead of static integrity audit and dynamic update audit while supporting the dynamic update of data integrity audit,and optimize the audit mechanism.performance.The data integrity audit method based on partial DHT authentication has lower communication overhead and calculation overhead when TPA completes large-scale batch data verification,thereby further improving the audit efficiency of the scheme.The research results have theoretical significance and reference value.