Software Engineering

FIGURE 18.1
The architecture definition stage.

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18.1 
Preliminary architecture definition
themes. Structural units must be specified in terms of their behavior, data elements, 
algorithms, conditional control mechanisms, interfaces, and fault detection and 
recovery procedures. This is accomplished by coalescing functional unit specifica-
tions while resolving conflicting or duplicative functional characteristics. A structural 
unit inheritance hierarchy should be developed to formulate how object-oriented 
characteristics will be transmitted from parent units to offspring. The software inte-
gration strategy must be established to bridge the design chasm between structural 
units and conceptual components. The structural user interface hierarchy must be 
established to identify the mechanism involving information displays, navigational 
controls, data formatting, and data entry mechanisms. Database queries must be 
specified that satisfy identified functional database transaction behaviors. Software 
test procedures and the plans for software implementation must be finalized.
The detailed architecture definition stage concludes with the critical design 
review (CDR). The CDR is intended to demonstrate that the physical architecture is 
complete, verified, and validated. The physical architecture must be verified against 
the functional architecture and against the software requirements baseline. The dis-
tilled structural unit specifications will guide the software implementation team in 
the design, coding, and testing of each software unit. The arrangement of structural 
units and components must be reviewed to ensure that the structural configuration 
is not unreasonably complex and will facilitate problem resolution and preplanned 
product improvements (P
3
I).