Data Protection and Security

V

Access Control

V.IV

Multilevel Security

Multilevel Security

Previous two examples are either too expensive to implement or too restrictive to satisfy more complex security requirements. For instance in military, two confidentiality levels are not sufficient. The following figure shows four confidential levels to label documents which is in use in NATO.

These levels can be either used for classification of documents (objects) or for giving clearances to users (subjects). For instance, in USA a secret clearance involves checking FBI fingerprint files.