Capability-based delegation model in RBAC

For flexible and dynamic resource management in environments where users collaborate to fulfill their common tasks, various attempts at modeling delegation of authority have been proposed using the role-based access control (RBAC) model. However, to achieve a higher level of collaboration in large-scale networked systems, it is worthwhile supporting cross-domain delegation with low administration cost. For that purpose, we propose a capability-role-based access control (CRBAC) model, by integrating a capability-based access control mechanism into the RBAC96 model. Central to this scheme is the mapping of capabilities to permissions as well as to roles in each domain, thereby realizing the delegation of permissions and roles by capability transfer. By taking this approach of capability-based access control, our model has the advantages of flexibility and reduced administration costs. We also demonstrate the effectiveness of our model by using examples of various types of delegation in clinical information systems.