Redundant data avoidance systems, the Private Cloud are involved as a proxy to allow data owner/users to securely perform duplicate check with differential privileges. Such architecture is practical and has attracted much attention from researchers. The data owners only outsource their data storage by utilizing public cloud while the data operation is managed in private cloud, in this connection our presented system has follows traditional encryption while providing data confidentiality, is incompatible with redundant data avoidance. Identical data copies of different users will lead to different ciphertexts, making data avoidance impossible. To address above issues convergent encryption technique has been proposed to encrypt the data before outsourcing. To better protect data security, this paper makes the first attempt to formally address the problem of authorized redundant data avoidance. Different from traditional redundant data avoidance systems, the differential privileges of users are further considered in duplicate check besides the data itself. We also present several new redundant data avoidance constructions supporting authorized duplicate check in a multi-cloud architecture. Security analysis demonstrates that our scheme is secure in terms of the definitions specified in the proposed security model. In order to perform secure access controlling scheme user may satisfy fine-grained approach at cloud level towards access restricting from unauthorized users or adversaries.

Kamarthi Rekha,G.Somasekhar,Dr S.Prem Kumar."Secure Redundant Data Avoidance over Multi-Cloud Architecture". International Journal of Computer Engineering In Research Trends (IJCERT) ,ISSN:2349-7084 ,Vol.2, Issue 08,pp.470-474, AUGUST - 2015, URL :https://ijcert.org/ems/ijcert_papers/V2I803.pdf,

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