Cloud Computing is an emerging service oriented domain which performs Primitive services as IaaS,PaaS and SaaS along with A Cloud database management system (CDBMS) is a distributed database that delivers computing as a service instead of a product is called as DBaaS (Database as a Service) . Improving confidentiality of information stored in cloud database it is an important contribution to cloud database. Data encryption is the optimum solution for achieving confidentiality. In some native method, encrypt the whole database through some standard encryption algorithm that does not allow the any sql operation directly on the cloud. This formal solution affected by workload and cost would make the cloud database service inconvenient. We propose a novel Flexible architecture for encryption of public cloud database as independent encryption architecture which performs double layer encryption in order to protect Cloud database as well user privacy with data integrity. Adaptive encryption allow any sql operation over encrypted data. The novel cloud database architecture that uses adaptive encryption technique with no intermediate servers. This scheme provides cloud provider with the best level of confidentiality for any database workload. We can determine the encryption and adaptive encryption cost of data confidentiality from the research point of view.

K. Sravani,D. Praveen Kumar."Performance and Cost Evaluation of Flexible Architecture with Double Layer Encryption". International Journal of Computer Engineering In Research Trends (IJCERT) ,ISSN:2349-7084 ,Vol.2, Issue 06,pp.395-399, June - 2015, URL :https://ijcert.org/ems/ijcert_papers/V2I63.pdf,

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