Software Engineering

Requirements
Definition
Implementation
Preliminary
Detailed
Code & Test
Integration
Product Testing
Acceptance
Testing
Software Development
Post-development Process Preparation
Computing Environment Preparation
Definition
Design
Implementation
Qulaification Supports software
Product Testing
Post-development Process
Operations
Distribution Oprations
Training Operations
Customer Support Operations
Product Support Operations
Process Definition
Process Design
Process Implementation
Qualification
Architecture Definition
FIGURE 5.1
Concurrent development of products and processes.

---

86
CHAPTER 5 
Software Integrated Product and Process Development
5.1.3 
Early and continuous life-cycle planning
The IPPD philosophy expands the definition of development to address the product 
life cycle. This involves more than the development of the product—establishing 
the infrastructure for post-development software sustainment. This involves con-
sidering how the product may be evolved over time through a number of iterative 
development efforts, as well as how the advancement of computing technology may 
affect the product design and computing environment composition. The variable 
element of the product life cycle must be identified early to ensure that the software 
product architecture is established to facilitate the product’s evolution. Planning  
the product development and life-cycle sustainment activities must begin early 
in the product conceptual definition. The planning activities must be revised to  
continually incorporate the most current knowledge and understanding of the effort 
needed to complete the initial product development and initiate the post-develop-
ment efforts.
This captures the premise behind iterative and incremental software devel-
opment approaches. They recognize that a software product will evolve through-
out its life cycle. Therefore, it is prudent to plan the software product’s evolution 
around several iterations of software development to provide increments of prod-
uct functionality and performance. Under the IPPD philosophy, the initial devel-
opment of the software product represents a large development effort due to the 
need to establish the product architecture. During software sustainment, the prod-
uct is modified, enhanced, or extended by additional iterations of the development 
activities. Whenever the software product must undergo significant architectural 
redefinition, a new software development project should be established. For each 
major iteration of software development, the associated life-cycle processes may 
need to be redeveloped to accommodate the changes in the product’s architecture. 
Figure 5.2
 shows the sequence and alignment of software development projects and 
post-development software sustainment iterations.
Software Development
Iteration 1
Software Sustainment
Iteration 1.1
Software Sustainment
Iteration 1.2
Software Sustainment
Iteration 1.3
Software Sustainment
Iteration 2.1
Software Development
Iteration 1.3
Revision 1.1
Revision 1.2
Revision 1.3
Revision 2.1
Product Version 1.0
Product Version 2.0
FIGURE 5.2
Iterative and/or incremental software life-cycle planning.

---