Scalable Role & Organization Based Access Control and Its Administration

SCALABLE ROLE & ORGANIZATION BASED ACCESS CONTROL AND ITS ADMINISTRATION Zhixiong Zhang, Ph.D. George Mason University, 2008 Dissertation Co-director: Dr. Ravi S. Sandhu Dissertation Co-director: Dr. Daniel Menascé In Role Based Access Control (RBAC), roles are typically created based on job functions inside an organization. Traditional RBAC does not scale up well for modeling security policies spanning multiple organizations. To solve this problem, a family of extended RBAC models called Role and Organization Based Access Control (ROBAC) models and its administrative models are proposed and formalized in this dissertation. Two examples are used to motivate and demonstrate the usefulness of ROBAC. Comparison between ROBAC and other RBAC extensions are given. I show that ROBAC can significantly reduce the administrative complexities of applications involving a large number of similar organizational units. The applicability and expressive power of ROBAC are discussed. By showing that any given ROBAC model can be modeled by a RBAC model and vice versa, I prove that the expressive power of ROBAC is equal to that of traditional RBAC. A comprehensive role and organization based administrative model called AROBAC07 is developed. It has five sub-models dealing with various administrative tasks in ROBAC. I show that the AROBAC07 model provides an intuitive and controlled way to decentralize administrative tasks in ROBAC based systems. A concept called application compartment (ACom) in ROBAC is introduced and its usage in ROBAC is discussed. AROBAC07 scales up very well for ROBAC based systems involving many organizational units. Two ROBAC variants, manifold ROBAC (ROBAC) and pseudo ROBAC (ROBAC), are presented and formalized. Their corresponding administrative models are also proposed. The usefulness of manifold ROBAC is demonstrated in secure collaboration via a ROBAC based secure collaboration schema which avoids many problems resulted from role-mapping, role-translation, or role exporting. The usefulness of pseudo ROBAC is demonstrated in a web based on-demand movie service case study.