Software Engineering

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CHAPTER 5 
Software Integrated Product and Process Development
address the manufacturing and assembly line capabilities to produce quantities of 
units with consistent dimensions, properties, or characteristics. Engineering toler-
ances must be specified to allow reasonable leeway for imperfections and inher-
ent variability in production quality without significantly affecting functioning of 
assembled components. Therefore, the engineering design specifications for hard-
ware parts must incorporate production process capabilities. Furthermore, the man-
ufacturing process must incorporate adequate process control devices to ensure a 
significant yield of acceptable parts and reduce manufacturing waste and rework. 
This demands that design engineers of products that must be manufactured must be 
cognizant of the capabilities of the production tooling and manufacturing process.
A software product is a complex “system” that is made up of many collaborating 
parts. It is not sufficient to simply decompose software requirements and allocate 
them to software components and units. Software IPPD must resolve design chal-
lenges and complexity by establishing the product architecture. The development of 
the functional architecture addresses software control flow, data exchanges, perfor-
mance, resource utilization, and detection and response to failure conditions. The 
physical architecture addresses the manner in which software structural units and 
components collaborate and are integrated to comprise the final software product. 
The software architecture represents the design of the software product with suffi-
cient information to permit structural units and component behaviors to be specified.
Software IPPD differs from traditional software development due to the nature 
of the software product of which the implementation design is dependent on the 
capabilities and programming constructs inherent in the compilation language. The 
software functional and physical architectures must be developed with an under-
standing of implementation and testing challenges. This requires the involvement of 
software implementation and testing subject matter experts in software engineering 
activities. In addition, the post-development software sustainment processes must 
be addressed so that they can be established and tested in a timely manner to sup-
port software product distribution. Therefore, the software engineering integrated 
product team (SWE-IPT) must involve representatives from all software technical 
organizations. This permits the software product architecture to be developed with 
an appreciation for software implementation and sustainment issues. This approach 
reduces life-cycle costs, minimizes risk to achieving project schedules, and restricts 
the potential for requirements creep.
Additionally, software engineering IPPD ensure that sufficient time is invested in 
establishing the product architecture where early design decisions can have the most 
significant impact on project and process success. During the architecture defini-
tion phases, design alternatives should be evaluated via modeling and prototyping to 
determine the best approach to proceed with. Prototyping should not be left until soft-
ware implementation because it defers important design decisions to later phases of 
development. Software implementation should be simplified to the design of software 
units against the specification established by the physical architecture. This approach 
is more consistent with hardware development where detailed models and equipment 
prototypes are developed during detailed design to confirm design suitability.

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Software Integrated Product and Process Development
Table 5.1
 aligns the traditional software development, software engineer-
ing, and hardware development phases to highlight the differences between these 
approaches. Notice that software implementation and the designing, coding, inte-
gration, and testing of the software product is aligned with the hardware fabrication 
phase. This alignment suggests that the software implementation effort is analogous 
to hardware manufacturing. Therefore, the predominance of the software product