Software Engineering

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13.1 
Design conceptualization
13.1.2 
Identify abstract structural components
Developing a conceptual design begins with the identification of abstract structural 
components. The top level of abstract components represents major containers for 
software functionality. These abstract components will provide the foundational 
elements upon which the design concept can be expressed, analyzed, and debated. 
Deliberation concerning the suitability of the design concept may result in the con-
cept evolving into a more appropriate design concept. As functional analysis pro-
ceeds, the initial design concept must be reevaluated to determine if it continues to 
embody the operational nature of the software product.
Abstract structural components should be labeled for their role in carrying out 
the principal threads of operational behaviors. An abstract component should pro-
vide a single, focused role within the structural design concept. However, there are 
no restrictions on how many roles an abstract component may assume responsibil-
ity for. When considering how to label an abstract component, the primary focus 
should be placed on how the assortment of abstract structural components should 
be arranged to facilitate their interaction while diminishing structural complexity.
The conceptual design layers should be captured as a software block diagram to 
depict the arrangement of abstract structural components and their interfaces (inter-
nal and external). Since the software configuration does not embody any physical 
dimension, the structural layout of abstract components should be based on the 
relative prominence of each component within the design concept. An abstract 
interface should be identified to initially represent the data exchange relationships 
among abstract components and with external systems. The software block diagram 
should present the conceptual design at various levels of deliberation to contend 
with the most decisive design challenges.
In the early stages of forming conceptual design it is not necessary to include 
every conceivable abstract component. The conceptual design is merely a device 
for organizing the structural configuration to reflect the emerging perception gained 
from the functional solution. It is beneficial to formulate several design concepts 
that accentuate different architectural solutions to determine the preferred concep-
tual design configuration. Alternative conceptual configurations must be evaluated 
to identify the most balanced solution regarding the functional architecture, stake-
holder requirements, and project cost and schedule constraints.