Abstract:
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.
