To preserve privacy and secure access control in Public cloud use of two layer encryption algorithms provides better result, but use of the secure hypertext transfer protocol and single sign on approach will increase the efficiency regarding security. It will help owner to improve communication and computation cost as the fine grain access control performed on cloud side and improves security. As an old approach has all the responsibilities of data owner to encrypt data and re-encrypt updated or modified data it incur a high computation cost. As Public cloud is third party so data owner are not able to trust on cloud for security purpose so fine grain access cannot get delegate to cloud side. To overcome this problem and increase security use of two layer encryption algorithms and secure Sockets Layer (SSL) along with Single sign on approach will provide better results.

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Identity Privacy Ssl Policy Decomposition Encryption Cloud Computing Access Control blowfish.