A top-level architecture
diagram work product, the
configuration diagram is a diagram that
documents the hierarchical configuration of all (or a part of
a) system in terms of its logical elements and the
decomposition relationships between them.
The following definitions can be used for the different
types of logical elements of a configuration diagram:
System of Systems
A cohesive set of integrated systems that collaborate
to accomplish a defined set of missions
System
A cohesive set of integrated elements that collaborate
to accomplish a defined mission
Subsystem
A defined part of a system consisting of a cohesive set
of integrated segments
Segment
A defined part of a subsystem consisting of a cohesive
set of integrated subsegments
Subsegment
A defined part of a segment consisting of a cohesive
set of integrated assemblies
Assembly
A defined part of a subsegment consisting of a cohesive
set of integrated subassemblies
Subassembly
A defined part of an assembly consisting of a cohesive
set of integrated configuration items
Configuration Item
A defined part of a subassembly consisting of a
cohesive set of integrated components that is designated
for separate configuration management
Component
A defined part of a configuration item consisting of a
cohesive set of integrated parts or units (and potentially
other lower-level components)
Part
The lowest level of separately identified hardware
items in the configuration
Computer Software Unit (CSU)
The lowest level of separately identified software
items in the configuration
The appropriate number of tiers in the configuration
hierarchy depends on the size and complexity of the system
being architected. Smaller and simpler systems may leave out
certain tiers (e.g., segments and subsegments, assemblies and
subassemblies).
Because configurations rapidly grow wider as you go down
the decomposition hierarchy, configuration diagrams are
typically :
Drawn in landscape rather than portrait mode.
Decomposed into a layered set of smaller, more
manageable diagrams.
