Preserving Consistency in Data Cloud Using Secure and Efficient Third Party Auditor

Cloud storage services have become very popular nowadays due to their immense advantages. To provide unique and updated always-on access, a cloud service provider (CSP) maintains multiple replicas for each piece of data on geographically distributed servers. The main problem of using the replication technique in clouds is that it is very expensive to maintain consistency among data. In this paper, a novel consistency as a service (CaaS) model is presented. It consists of a large data cloud and multiple small audit clouds. The audit cloud helps us to check whether consistency is maintained. In this model, a two-level auditing architecture is used, which only requires a loosely synchronized clock in the audit cloud. A heuristic auditing strategy is to be devised in order to reveal possible violations. In cloud, consistency influences the availability and performance of the system. To check the consistency, auditing is done where the data/report is evaluated to determine whether the cloud server safeguards the data, maintains consistency. The election of best suitable auditor for the auditing purpose will help improve in maintaining the consistency level of the data in the cloud.