An object-oriented model of access control based on role

At present, majority access control models mainly deal with data-protection at the back-end of applications. However, they are not applicable for large and complex multi-user applications. Though Object Technology has turned into one of the mainstream approaches for large and complex applications development, it still lacks a general model of application-level access control. While the existing models of role-based access control could simplify privilege management, they neglect the dynamic features of activated roles. This paper proposes an object-oriented model in Unified Modeling Language supporting application-level access control based on users' roles. In the model, an interface type is provided containing a set of operations as user services, which are authorized to users via their roles. To represent the activated roles, Role-Playing is introduced, and it is modeled as an active class. Every object of Role-Playing runs in particular context, which restrict users' rights dynamically and control users' interaction actively. The model is suitable for multi-user interactive computing and distributed information-processing systems.