Outsourcing data to a third-party administrative control, as is done in cloud computing, gives rise to security concerns. The data compromise may occur due to attacks by other users and nodes within the cloud. Therefore, high security measures are required to protect data within the cloud. However, the employed security strategy must also take into account the optimization of the data retrieval time. In this paper, we propose Division and Replication of Data in the Cloud for Optimal Performance and Security (DROPS) that collectively approaches the security and performance issues. In the DROPS methodology, we divide a file into fragments, and replicate the fragmented data over the cloud nodes. Each of the nodes stores only a single fragment of a particular data file that ensures that even in case of a successful attack, no meaningful information is revealed to the attacker. Moreover, the nodes storing the fragments, are separated with certain distance by means of graph T-coloring to prohibit an attacker of guessing the locations of the fragments. Furthermore, the DROPS methodology does not rely on the traditional cryptographic techniques for the data security; thereby relieving the system of computationally expensive methodologies.
 K. Bilal, M. Manzano, S. U. Khan, E. Calle, K. Li, and A. Zomaya, “On the characterization of the structural robustness of data center networks,” IEEE Transactions on Cloud Computing, Vol. 1, No. 1, 2013.  Y. Deswarte, L. Blain, and J-C. Fabre, “Intrusion tolerance in distributed computing systems,” In Proceedings of IEEE Computer Society Symposium on Research in Security and Privacy, Oakland CA,110- 121, 1991  B.Grobauer, T.Walloschek, and E. Stocker, “Understanding cloud computing vulnerabilities,” IEEE Security and Privacy, Vol.9, No. 2, 2011.  W. K. Hale, “Frequency assignment: Theory and applications,” Proceedings of the IEEE, Vol. 68, No. 12, 1980,  K. Hashizume, D. G. Rosado, E. Fernndez-Medina, and E. B. Fernandez, “An analysis of security issues for cloud computing,” Journal of Internet Services and Applications, Vol. 4, No. 1,2013,  W. A. Jansen, “Cloud hooks: Security and privacy issues in cloud computing,” In 44th Hawaii IEEE International Conference on System Sciences (HICSS), 2011,  A. Juels and A. Opera, “New approaches to security and availability for cloud data,” Communications of the ACM, Vol. 56, No. 2, 2013.  L. M. Kaufman, “Data security in the world of cloud computing,” IEEE Security and Privacy, Vol. 7, No. 4, 2009, pp. 61-64.  L. Qiu, V. N. Padmanabhan, and G. M. Voelker, “On the placement of web server replicas,” In Proceedings of INFOCOM 2001, Twentieth Annual Joint Conference of the IEEE Computer and Communications Societies, Vol. 3, pp. 1587-1596, 2001.  D. Sun, G. Chang, L. Sun, and X. Wang, “Surveying and analyzing security, privacy and trust issues in cloud computing environments,” Procedia Engineering, Vol. 15, 2011, pp. 2852 -2856.
Centrality, cloud security, fragmentation, replication, performance.