Multi-level access control for collaborative CAD

Access control is one of the key steps to ensuring the availability, confidentiality and integrity of system resources. While it has been fully applied in various network systems, it's still relatively new for collaborative CAD. This paper provides a new framework of multi-level access control for collaborative CAD based on hierarchical product modeling. A layered privilege model (LPM) has been developed to provide multi-granularity access permissions in the part level and feature level. An extended hierarchy role-based access control (EHRBAC) is implemented, integrated with LPM and common Hierarchy RBAC, to provide hierarchical access control of collaborative feature modeling in the component/part level and design feature level. Mesh simplification techniques are used to create variable level-of-detail for individual features.