An Overview of Data Access Control in Security for Multi authority Cloud Storage Systems

Cloud computing technologies get more importance with a high level in secure data access control in a semi-trusted cloud storage system. Data access control for multi authority cloud storage systems (DAC-MACS) is a beneficial way to ensure data security of the cloud storage system. The two main challenging issues of the current cloud storage systems are data outsourcing and untrusted cloud servers. However, cloud storage service separates the roles of the data owner from the data service provider, and the data owner does not interact with the user directly for providing data access service, which makes the data access control a challenging issue in cloud storage systems. Because the cloud server cannot be fully trusted by data owners, traditional server-based access control methods are no longer applicable to cloud storage systems. To prevent the untrusted servers from accessing sensitive data, traditional methods usually encrypt the data and only users holding valid keys can access the data. In this research work, survey is conducted towards the attacks on data access control scheme for multi-authority cloud storage system. The security improvements of secret key generation and attribute revocation in data access control scheme to be corrected. Finally, the major overhead of decryption is also securely outsourced to the cloud servers, and the overall overheads of storage, communication and computation of the NEDAC-MACS are superior to that of DACC and relatively same as that of DAC-MACS. The analysed methodologies are implemented using the CloudSim toolkit, which is evaluated to know the performance of every research works. The performance evaluation conducted was proved that the each method has unique advantage and disadvantages among each other.