Data storing and sharing becomes a most important exceptionally attractive service supplied by cloud computing platforms because of its convenience cost effective platform and more economy. Data owner to store and outsourcing their data in the cloud and through which provide the data access to the user However, outsourcing data to a third-party administrative control entails serious security concerns. Cloud client upload Data leakage may be occur due to attacks by other users and machines in the cloud. Data leakage is and data privacy strategies an ongoing problem in the field of cloud security. The proposed work identifies security and privacy issues for secure data management in cloud environment. The proposed system provides a novel effective scheme that is named as HSDS-DP (High Secure Data Share with dynamic policy update), which is a new technique for data privacy with improved security features. The proposal has three main contributions such as, Threshold Secret Sharing, Dynamic access control update, and key managers. The proposed method Client receives public keys from all Key Managers (KM), afterwards client generate random symmetric-key for perform encryption, Symmetric key are protected by the public key. Encrypted data and keys are uploaded in the cloud. For accessing the file client should download encrypted entire key share and encrypted data file from cloud. Accessing the data client send share of key to the Key Managers, so that client will receives backs decrypted share. Proposed Dynamic Access Policy Update Scheme so client dynamically updates the data access making request to cloud server. The results reveal that proposed can be effectively used for security of outsourced data by employing key management, access control, and file dynamic access policy updating process. Our proposed scheme can prevent cheating and Data leakage problem in public cloud infrastructure.

Data security, Access Control, Secret Sharing, Cloud computing, Semi-Trusted Third Party, key management

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