Fig. 1From: A new usage control protocol for data protection of cloud environmentTraditional access control model. The technology stipulates whether the subject can access to the object through the authorization policy. There are three main strategies: discretionary access control (DAC), mandatory access control (MAC), and role-based access control (RBAC). All of them have been widely used in various fields of DRM. They are all based on the subject-object passive security modelBack to article page