id: "SA-08(04)" title: "Partially Ordered Dependencies" family: "SA" family_name: "System and Services Acquisition" sort_id: "sa-08.04" priority: "P1" implementation_level: "system" parent: "SA-08" enhancement: True
Statement
Implement the security design principle of partially ordered dependencies in {{ insert: param, sa-08.04_odp }}.
Guidance
The principle of partially ordered dependencies states that the synchronization, calling, and other dependencies in the system are partially ordered. A fundamental concept in system design is layering, whereby the system is organized into well-defined, functionally related modules or components. The layers are linearly ordered with respect to inter-layer dependencies, such that higher layers are dependent on lower layers. While providing functionality to higher layers, some layers can be self-contained and not dependent on lower layers. While a partial ordering of all functions in a given system may not be possible, if circular dependencies are constrained to occur within layers, the inherent problems of circularity can be more easily managed. Partially ordered dependencies and system layering contribute significantly to the simplicity and coherency of the system design. Partially ordered dependencies also facilitate system testing and analysis.
Assessment Objective
{{ insert: param, sa-08.04_odp }} implement the security design principle of partially ordered dependencies.
System and services acquisition policy
procedures addressing the security design principle of partially ordered dependencies used in the specification, design, development, implementation, and modification of the system
system design documentation
security and privacy requirements and specifications for the system
system security and privacy architecture
system security plan
other relevant documents or records
Organizational personnel with the responsibility for determining system security and privacy requirements
organizational personnel with system specification, design, development, implementation, and modification responsibilities
system developers
organizational personnel with information security responsibilities
Organizational processes for applying the security design principle of partially ordered dependencies in system specification, design, development, implementation, and modification
mechanisms supporting the application of the security design principle of partially ordered dependencies in system specification, design, development, implementation, and modification