Military ADP systems in the US are generally divided into 4 modes of operation, each with different sets of management aspects for each of a number of requirements. Figure 1 contains a broad summary of their requirements.
Figure 1 - Summary of Security Requirements |--------------------------------------------------------------------| |Requirement | Mode of Operation | | |----------------------------------------------------| | | Dedicated | System high | Controlled | Multilevel | |--------------------------------------------------------------------| | Individual | Physical access controls | Physical access controls| | Accountability| for central computer | for central computing | | | facility and all ADPS | facility and access to | | | resources |terminal areas restricted| | |--------------------------| to top level displayed | | |Color change| Internal |-------------------------| | |for periods | Controls for|Nonmalicious| Security | | |processing | Need-to-know| users | Kernels | | | | |------------| | | | | |< 4 adjacent| | | | | | clearance | | | | | | categories | | | | | |------------| | | | | | Internal OS| | | | | | Security | | | | | | Controls | | | | | |------------| | | | | | Procedural | | | | | | Constraints| | | | | |------------| | |--------------------------------------------------------------------| | Physical | Physical protection for | Physical protection for | | Control |central computer facility |central computer facility| | | and all ADPS resources | Restricted access to | | | | terminal areas ala top | | | | security level displayed| |--------------------------------------------------------------------| | System | Physical access controls, Hardware features, | | Stability | Software error mechanisms, operational procedures | |--------------------------------------------------------------------| | Data Integrity| Software features | |--------------------------------------------------------------------| | System | Physical access controls | | Reliability |----------------------------------------------------| | | | Internal | OS Controls| Security | | | | Controls for| Operational| Kernels | | | | Need to know| Constraints| | |--------------------------------------------------------------------| | Communication | Encryption, Protected wire distribution systems, | | Line | protected switches and circuits | | Protection |----------------------------------------------------| | |Not required| | | | | | inside | | | | | | physically | | | | | | controlled | | | | | | area | | | | |--------------------------------------------------------------------| | Classified | Security classification markings, declassification | | Material | procedures, operational procedures, software/data | | Protection | format features | | |----------------------------------------------------| | |Color change| Internal | Internal OS| Security | | | for periods|controls for | security | Kernels | | | processing | need to know| controls | | |--------------------------------------------------------------------|