1. © 2005 Ravi Sandhu www.list.gmu.edu Permissions and Inheritance (best viewed in slide show mode) Ravi Sandhu Laboratory for Information Security Technology George Mason University www.list.gmu.edu sandhu@gmu.edu

2. © 2005 Ravi Sandhu www.list.gmu.edu 2 Reference Jason Crampton. On permissions, inheritance and role hierarchies. Proceedings of the 10th ACM conference on Computer and communications security, Washington D.C 2003, pages: 85-92 Several diagrams and text excerpts are taken directly from this paper.

3. © 2005 Ravi Sandhu www.list.gmu.edu 3 Arrow notation

4. © 2005 Ravi Sandhu www.list.gmu.edu 4 Administrative scope

5. © 2005 Ravi Sandhu www.list.gmu.edu 5 Effective roles of permission p up down neutral

6. © 2005 Ravi Sandhu www.list.gmu.edu 6 Permission Hierarchy

7. © 2005 Ravi Sandhu www.list.gmu.edu 7 Consistency and redundancy

8. © 2005 Ravi Sandhu www.list.gmu.edu 8 Simulating BLP (liberal *-property)

9. © 2005 Ravi Sandhu www.list.gmu.edu 9 Simulating BLP (liberal *-property) Maximal or minimal permission is assigned to exactly one role

10. © 2005 Ravi Sandhu www.list.gmu.edu 10 Constraints for simulating BLP

11. © 2005 Ravi Sandhu www.list.gmu.edu 11 Constraints for simulating BLP

12. © 2005 Ravi Sandhu www.list.gmu.edu 12 Constraints for simulating BLP

13. © 2005 Ravi Sandhu www.list.gmu.edu 13 Constraints for simulating BLP

14. © 2005 Ravi Sandhu www.list.gmu.edu 14 Constraints for simulating BLP

15. © 2005 Ravi Sandhu www.list.gmu.edu 15 Security levels

16. © 2005 Ravi Sandhu www.list.gmu.edu 16 Security levels