基于区块链的云数据删除验证协议

Blockchain-Based Verification Scheme for Deletion Operation in Cloud

云服务器可以为用户提供任何时间、任何地点的服务,并极大地降低用户成本,提高使用的便利性,如今越来越多的用户将自己的数据存储在云服务器.然而,关于云存储中的安全问题不时得到披露,影响到用户对云存储的信任,因此必须足够重视云存储及云服务中的安全问题.例如未经身份验证的用户不可以访问云服务器,云服务器不按用户的要求删除数据应该能被发现并惩罚.为了解决这些问题,提出了一种基于区块链的云数据删除验证协议.首先,用户通过调用智能合约向云服务器证明自己的身份,并且创建数据删除的请求交易,然后云服务器删除数据并生成一条嵌有删除证据的区块链(证据链).无论云服务器是否恶意,用户都可以验证数据删除结果.安全性分析表明:提出的协议可以在没有第三方可信机构的情况下完成数据的公开验证,同时可以抵抗窃听攻击、假冒攻击等.

Nowadays,more and more users upload their data to the cloud server,since the cloud can provide the service for users any time and at any place.Therefore,the cloud service facilitates the data usability and reduces the cost.However,the information leakage accidents have been reported frequently over the world,that is to say the cloud server is not fully trusted,and the security issue in cloud service must be paid enough attention.For example,illegal user may want to access the cloud server,and perhaps the cloud server does not delete the data according the user s requirement.In order to address these concerns,a verification scheme for deletion operation in cloud is presented using block-chain technology,which can make the deletion operation more transparent.In our scheme,the user calls the smart contract to prove his identity to the cloud server,and creates the request transaction for data deletion;then the cloud server deletes the data and generates a block chain with the evidence(evidence chain).Even if the cloud server is dishonest,the user can still verify the data deletion result.Moreover,the proposed scheme is analyzed to really achieve the public verification of data without the third-party trusted organization,the impersonation attacks resistance,and the eavesdropping attacks resistance,etc.