Research On Computing-Efficient And Publicly-Verifiable Cloud Storage Integrity Checking Schemes

Along with the rapid development of cloud computing platforms,cloud storage services are becoming widespread in recent years.These services greatly reduce the burden of clients,while it also brings certain security risks to the cloud data,such as the risk of data corruption.In order to verify the integrity of the cloud data,a mass of cloud storage integrity checking schemes have been put forward one after another,but these schemes generally either involve complex bilinear pairings,or do not support public verifiability.In addition,the data stored in the cloud server might involve a number of sensitive information.However,the existing researches in this area also work inefficiently.In view of the above problems,this thesis designs various computing-efficient new schemes.(1)This thesis designs a publicly-verifiable cloud storage integrity checking scheme based on the discrete logarithm.This scheme applies simple algebraic operations to implement integrity checking,removing the habitual bilinear pairings and complex hash functions.This scheme is secure in the random oracle model under the discrete logarithm assumption.Compared to the two classic schemes,the file tag calculation efficiency of the designed scheme is improved by at least 200 times.When the file size is 64 MB and the number of challenged blocks is 460,the proof verification efficiency of the designed scheme is improved by at least 2.1 times.(2)This thesis designs a publicly-verifiable cloud storage integrity checking scheme with sensitive information hiding.On the basis of the first scheme,the designed scheme applies the existing sensitive information processing technology to realize that the data integrity can be still efficiently checked under the premise that the sensitive information of cloud data is hidden.The designed scheme is secure in the random oracle model under the discrete logarithm assumption.Experiment results show that when the file size is 64 MB,the tag generation time of the designed scheme is only 174.98 seconds,and the integrity checking of 460 challenged blocks only takes 453.62 milliseconds.