Software Engineering

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CHAPTER 18 
Software Architecture Definition
 2. 
Functional hierarchy.
 The functional hierarchy stipulates the layered break-
down of functional complexity to elementary, uncomplicated functions. 
Topmost functional components are decomposed into lower-level components 
to provide a logical framework for deriving software behaviors. Lower-level 
functional components must be further decomposed until functional units are 
perceived. Functional units represent elementary functions that can no longer 
be decomposed or of which the effective and efficient formulation does not 
warrant further exploration or decomposition.
 3. 
Database transaction behavior diagrams.
 Provides a behavioral representation 
of each database transaction the software product must support. These dia-
grams should identify the database tables accessed, the expected responses to 
transaction queries, and transaction rollback procedures.
 4. 
User interface functional hierarchy.
 This hierarchy depicts how common user 
interface functional mechanisms have been grouped into functional compo-
nents, subcomponents, and finally to functional units.
 5. 
Conceptual component block diagram.
 This diagram provides a layout of con-
ceptual components, the interfaces among components, and interfaces with 
operators and elements of the computing environment.
 6. 
Software test cases.
 The software test cases should be identified by tracing 
operational threads of behavior in the operational model. Each operational 
thread represents a unique test case. Each test case should identify the set of 
conditions under which a data processing transaction is exercised and the crite-
ria for determining that the transaction has been satisfied.
 7. 
Updated requirements traceability matrix.
 The requirements traceability matrix 
must be updated to reflect the evolving elements of the functional and physical 
architectures and software test cases.
 8. 
Updated nomenclature register.
 The software architecture dictionary must  
be updated to reflect the elements of the functional and physical  
architectures.
 9. 
Preliminary software implementation plan.
 The software implementation plan 
should be drafted to establish the level of effort and resources that will be nec-
essary to accomplish the implementation stage of the software development 
effort. The implementation plan should provide a basis for refining the related 
work packages to reflect the evolving software architecture and establish the 
resource allocations among subpackages. In addition, the software implemen-
tation plan should identify the staffing requirements for the software imple-
mentation organization including the types of skills that will be necessary to 
properly implement the software architecture.
10. 
Preliminary computing environment implementation plan.
 The computing 
environment implementation plan should be drafted to establish the level of 
effort and resources that will be necessary to establish the computing environ-
ment. The computing environment implementation plan will provide the basis 
for refining the related work packages to reflect the resource requirements for 
the computing environment implementation organization.

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