Research of ABAC model based on usage control under cloud environment.

To solve the problem of decision discontinuity and the problem of authorization inflexibility exist in the attribute based access control model under the cloud environment, this paper proposed a kind of improved attribute based access control model. What was more, it introduced the concepts of obligation and condition in usage control and the concept of meta state into the model. The improved model realized flexible and continuous authorization through the monitoring of obligation set which could complete the state transition and then trigger the authorization. The research studied the improved model from two aspects of formal definition and security analysis. Its corresponding advantages were also analyzed. Compared with the traditional model, the model has higher security and a more flexible way of authorization. It is more suitable for the cloud environment. [ABSTRACT FROM AUTHOR]