Research On Outsourced Data Auditing With Privacy-preserving In Cloud Computing

With the development of ICT(Information and Communication Technology),the traditional paper-based communication and information interacting modes have gradually step down from the stage of history due to many limitations.At present,almost all organizations,agencies and individuals mainly rely on computers connected to the Internet and intelligent communication devices for information transmission and communication,which leads to the gradual increase of data volume at the local sides of users.However,the local devices with constrained resources of storage and limited capability of computing cannot meet the requirements of sustainable data storage and processing.Cloud computing is a new network-based computing model that integrates distributed resources and provides users with a variety of virtualization services via the Internet.The rapid development of cloud computing and its advantages are of great use value in real-time data storage and processing.However,the data stored in the cloud is more vulnerable to security threats because the cloud servers are not fully trusted.If the data is not stored and processed properly due to security issues in the cloud,it will not only cause losses to personal property and national public property,but also seriously affect personal safety,thus affecting national and social stability.Hence,how to realize the auditing of the integrity of the data stored in the cloud in real-time that is not only of great practical significance,but also of theoretical value for the research of data storage security.In this dissertation,the issue of outsourced data auditing with privacy-preserving in cloud computing is studied.The main works included in this dissertation are summarized as follows:1)To reduce the computational overhead of data block preprocessing for lightweight users,the technique of the blind signature is used to design the auditing scheme that supports the computation outsourcing of data block signatures.In the proposed scheme,the user needs to blind the data blocks and then delegates the signatures computation of the blinded data blocks to the TPA.In order to ensure the validity of the received data block signatures,the BLS signature is used in the design of the proposed scheme that can verify the correctness of the blinded signatures computed by the TPA.Compared with the previous schemes,the proposed scheme can greatly reduce the computational cost of the user side.2)In this dissertation,the auditing of the verifiable database in cloud computing is studied.By using the polynomial commitment in the proposed scheme,the data in the cloud can be mapped to the data index values,which prevents the disclosure of the original data content in the auditing of the database.In addition,by using the index hash table to manage the data index and combining the BLS signature in the scheme construction,the proposed scheme not only provides the dynamic operations of the database,but also allows the data owner to verify the results of the dynamic operations of the database.The proposed scheme supports secure and efficient data storage integrity and correctness auditing,and can provide public verifiability with secret key exposure resistance,which provides high security assurance for the database storage in cloud computing.3)To solve the problem of data storage optimization in cloud services,the auditing scheme that supports cloud data duplicate detection and original data recovery is proposed in this dissertation.By using the message-locked encryption,users in the system can detect the duplication of the data before the data outsourcing,which can avoid the data redundancy.Moreover,the technique of the homomorphic verifiable authenticator(HVA)is used to build data blocks in the proposed auditing,which ensures users to delegate the auditing tasks to the TPA without obtaining the data blocks.In addition,the technique of erasure coding is used in the design of the data recovery mechanism that enables users to recover the deleted and corrupted data blocks in the cloud.