Towards secure dynamic collaborations with group-based RBAC model

Role-Based Access Control (RBAC) has become a popular technique for security purposes with increasing accessibility of information and data, especially in large-scale enterprise environments. However, authorization management in dynamic and ad-hoc collaborations between different groups or domains in these environments is still an unresolved problem. Traditional RBAC models cannot solve this problem because they cannot support security policy composition from different groups, and lack efficient administrative models for dynamic collaborations. In this paper, we propose a group-based RBAC model (GB-RBAC) for secure collaborations which is based on RBAC96 and extended with group concept to capture dynamic users and permissions. We propose a decentralized security administrative model for GB-RBAC to address the management issues of RBAC in collaborations. As a unique property, our model supports two levels of authorization management: global or system level management by system administrators and local or group level management by group administrators. In this way, our model implements the principles of management autonomy and separation of duty (SoD) in security administrations. We apply our model for authorization management in collaborations by introducing the concept of virtual group. A virtual group is built for a collaboration between multi-groups, where all members build trust relation within the group and are authorized to join and perform operations for the collaborative work. Compared with existing work, our model supports dynamic and ad-hoc collaborations in large-scale systems with the properties of controllable, decentralized, and fine-grained security management.