Research On Data Integrity Verification Technology In Cloud Storage

For the rapid development of internet technology in recent years,the data need to be dealt with presents an explosive growth,massive data storage and huge requirement for computing have become the main burden for ordinary users.Cloud computing has gradually been favored by users because of its security,reliability,scalability and high cost performance.Cloud storage service is one of the core services of cloud computing.More and more individuals,companies and organizations choose to manage their data on remote servers.However,users are not able to manage cloud files as what they do local files.For this reason,the Cloud storage,as a new data storage architecture,faces new challenges in terms of data security and manageability.Currently,cloud data security research is focusing on data integrity,confidentiality,and availability.Data integrity,which guarantees the integrity and correctness of users' data stored in cloud storage platforms,is a hotspot of related research.This thesis focus on the research of cloud data integrity verification,then proposes prospective theories,and completes engineering practice suitable for the current conditions.The three main works of this thesis are as follows.Firstly,considering the lack of computing power of end users or mobile users,a lattice-based data integrity verification scheme for mobile cloud computing is constructed by combining the lattice-based proxy signature and existing verification schemes.In the scheme,the third party with strong computing power is used instead of the user to generate authentication labels,which reduces the computational pressure of the user and expands the application mode.Security analysis shows that the scheme can resist common attack types.Secondly,in order to satisfied users' dynamic change requirements for cloud data,this thesis proposes a lattice-based dynamic verification scheme which is based on the combination of an improved signature method schemes and ranked Merkel Hash tree(RMHT).The scheme realizes data fine-grained signature,which can reduce the user's consumption of generating authentication labels,and achieves fine-grained dynamic operation.In addition,the verification work of dynamic operation in the scheme is delegated to the third party,which reduces the computing and communication costs of users.Finally,security analysis and performance analysis show our scheme not only has the characteristics of unforgeability and privacy protection,but also greatly reduces the computational cost of signature.Thirdly,this thesis designs and implements a prototype system of cloud dat a integrity verification on a cloud storage platform built by HDFS.This system not only realizes the users' basic modification operation and integrity verification of data,but also achieves the ability to protect users' data privacy by combinin g cryptographic techniques such as symmetric encryption and searchable encrypti on.