Research On Data Audit Technology In Cloud Environment

The advent of cloud computing aroused the flourish of many fields,bringing a convenient way to share data.That promoted the development of research,especially in the fields of data analysis,artificial intelligence,etc.However,security problems in the cloud environment happened with the benefits of the cloud.The integrity of data in the cloud is one of those.Though cloud service provider had employed some security mechanisms,such as anti-disaster backup,to protect the user's data,the data in the cloud is still at the risk of being corrupted due to hardware/software failures and human errors.In view of this issue,this thesis focuses on the integrity auditing for data in the cloud,spotlighting the problem of shared data auditing,such as sensitive information hiding and malicious manager preventing.Our contribution consists of three parts as follows.(1)A secure integrity auditing scheme for shared cloud data with sensitive information hiding is proposed.A novel system model is introduced to improve security in cases where managers could not be trusted in previous related work.It is the proposed scheme that enables the integrity and authenticity of data to be trusted by data owners and researchers.This model has less cost of computation at the manager side and is more suitable for high concurrency in the real scenario.(2)In order to solve the complex certificate management in the scheme(1),an identity-based signature algorithm is presented to design an aggregated signature.And With this basic,we construct an identity-based auditing scheme,which supports sensitive information hiding.More security system model is employed in the scheme,compared with the related work.In a new mechanism for sensitive information hiding,a part of the user,s secret key,instead of a random value,is used to hide sensitive information.That avoids the problem that files can be recovered and takes less storage cost.Besides,in this scheme,the user can directly retrieve data from the cloud,rather than sends a request to the manager.(3)For auditing the data integrity produced in the wireless body sensor network(WBSN),an auditing scheme based on certificateless proxy signature(CPS)for WBSN is proposed.This scheme also supports the property of sensitive information hiding for shared data.But an issue caused by supporting this property is that a blinded filed generated by file owner can be used by other users in the system.Thus,we introduced the CPS mechanism to sign files for file owners.And,security analysis guardians our scheme is able to prevent a malicious PKG,solving key escrow in the Identity-based scheme.Performance analysis and comparison experiments demonstrate that this scheme is as efficient as other CL-based schemes while achieving the aforementioned functions.