Software Engineering

FIGURE 2.2
Layers of software components within the SBS.

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33
2.1 
Software breakdown structure
an element that is comprised of two or more software units and/or components, as 
depicted in 
Figure 2.3
.
The challenge presented by this breakdown view is why there is a need to dif-
ferentiate the term 
software
 from 
software product
. Is the association with the com-
puting environment significant enough to transmit the meaning associated with the 
terms 
product
, 
component
, and 
unit
? This is better explained by examining the con-
cept behind software development. Just like the architect addresses the design of 
a house, there are other aspects of the construction effort beyond the design of the 
house itself. Things that must be considered involve positioning the structure of the 
house onto a plot of land, access to a street, a source electrical power, water, and 
sewage. These peripheral factors affect the design of the house and its structure and 
must be integral to the overall architectural aptitude and exactness.
The peripheral factors that must be addressed during software development 
involve how the software product will be sustained after the product is released, 
delivered, installed, and deployed. The systems engineering branch of knowledge 
has formulated an integrated product and process development concept to address 
the concurrent engineering of the product and life-cycle sustainment concepts. 
When this paradigm is applied to software it captures the peripheral factors associ-
ated with the post-development processes. Just like software development can be 
referred to as a development process, software product distribution, user operational 
training, and product support and maintenance can be regarded as processes. The 
inclusion of the integrated product and process development (IPPD) concept within 
the SBS results in a software hierarchy identified by 
Figure 2.4
.
FIGURE 2.3
Layers of software components and units within the software breakdown structure.

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