Software Engineering

21
1.10 
Configuration management and change control
●
  Cost and schedule objectives compel a project to make progress toward its 
conclusion. External forces, such as customer and stakeholder needs and expec-
tations, computing technology, competition, and market conditions, apply pres-
sure for the project to divert from established plans.
These assertions suggest that project management and software engineer-
ing practices should be established in a manner that governs these diametrically 
opposed forces. The goal-driven nature of a development project is focused on 
developing and delivering a quality software product in a timely and cost-effective 
manner. This warrants a strategy envisioned to insulate the project from sources of 
change. The nature of the marketplace suggests that the software development pro-
ject must be cognizant of the ever-changing conditions occurring in the environ-
ment that will ultimately determine the acceptability and success of the software 
product. The enterprise invests in the project by providing the people, facilities, 
tools and equipment, and resources necessary for the project to be conducted. 
Because of its investment, the enterprise desires to recognize a profit from the soft-
ware product, or it may aspire to improve its reputation within its industry as a reli-
able software development organization.
To properly cope with the dynamic forces of change, the central software engi-
neering philosophy must support a technical approach that facilitates the following 
principles:
1. 
Change is inevitable! It is necessary to be able to distinguish which changes are 
beneficial to adopt and which changes should be resisted or delayed until future 
versions of the product.
2. 
Changes that are adopted must be able to be incorporated into the planning, 
budgeting, and product configuration with a minimal amount of rework or 
schedule interruption.
3. 
Every change represents a form of rework, unless the change is a totally new 
requirement that does not interact with any other element within the software 
architecture. However, even such an isolated change will require the project 
plans and schedules to be updated to incorporate the revised work scope into 
work packages.
4. 
Change affects the software architecture involving the software product or the 
computing environment within which it is intended to operate. Change analysis 
should be performed to understand the perceived impact caused by a change to 
support a project determination to adopt the change. Depending on the state of 
the software development effort, the amount of rework involved with incorpo-
rating a change will vary significantly. In some instances, a change may require 
reperforming work that has already been accomplished. The scope of a change 
can be determined by assessing the number of elements and interfaces within 
the software architecture that are affected. This will provide an indication as to 
the amount of existing design and implementation work that must be redone. 
Review of the specification and documentation tree will support the change 
impact determination.

---