Security Enhancement of Data in Cloud using Fragmentation and Replication

Cloud computing technology, since its emergence, has found many applications in various fields. In cloud storage system, client stores data in cloud server and can work with the data anytime with ease. Due to availability of services with minimum cost and easy scalability, many organizations and enterprises make use of this cloud technology to reduce the maintenance cost and also to increase the reliability of data. But this technology has many security issues because data is outsourced to a third party administrative authority. Data leakage may occur due to attacks by other users and nodes. Therefore some security measures must be employed to take care of this security issues and this security measure or strategy must also take into account the performance of the system in terms of time required to retrieve the data. In this paper, we propose a system i. e. Fragmentation and Replication of data in cloud (FRDC) which addresses these issues related to security and performance. In this methodology, file uploaded by the client is first encrypted, and then this file is divided into fragments. Afterwards replications of these fragments over the cloud nodes take place. This process of fragmentation and replication is done in such a way that only a single fragment is stored on each node. Due to this process, even in case of successful intrusion of a node by an attacker, no significant information is revealed to the attacker. To further increase the security, T-coloring graph method is used. Due to this T-coloring graph method, it becomes difficult for an attacker to breach the security.