Which of the following is based on the premise that the quality of a software product is a direct function of the
quality of its associated software development and maintenance processes?

A.
The Software Capability Maturity Model (CMM)

B.
The Spiral Model

C.
The Waterfall Model

D.
Expert Systems Model

Explanation:
The Software Capability Maturity Model (CMM) is based on the premise that the quality of a software product is
a direct function of the quality of its associated software development and maintenance processes. It introduces
five maturity levels that serve as a foundation for conducting continuous process improvement and as an
ordinal scale for measuring the maturity of the organization involved in the software processes.
CMM has Five Maturity Levels of Software Processes:
The initial level: processes are disorganized, even chaotic. Success is likely to depend on individual efforts,
and is not considered to be repeatable as processes would not be sufficiently defined and documented to
allow them to be replicated.
The repeatable or managed level: basic project management techniques are established, and successes
could be repeated as the requisite processes would have been made established, defined, and
documented.
The defined level: an organization has developed its own standard software process through greater
attention to documentation, standardization, and integration.
The quantatively managed level: an organization monitors and controls its own processes through data
collection and analysis.
The optimized level: processes are constantly being improved through monitoring feedback from current
processes and introducing innovative processes to better serve the organization’s particular needs.
Incorrect Answers:
B: The Spiral model uses an iterative approach to software development with an emphasis on risk analysis. The
iterative approach allows new requirements to be addressed as they are uncovered. Testing takes place early
in the development project, and feedback based upon these tests is integrated into the following iteration of
steps. The risk analysis ensures that all issues are actively reviewed and analyzed. The evaluation phase
allows the customer to evaluate the product in its current state and provide feedback, which is an input value for
the following iteration of steps. This is a good model for complex projects that have fluid requirements.
C: The Waterfall model uses a linear-sequential life-cycle approach with each phase having to be completed in
its entirety before the next phase can begin. At the end of each phase, a review takes place to make sure the
project is on the correct path. In this model all requirements are gathered in the initial phase and it is difficult to
integrate changes as more information becomes available or requirements change.
D: Expert systems is not a model for the development of software products. It is the use artificial intelligence
(AI) to solve problems and is also called knowledge-based systems.

Harris, Shon, All In One CISSP Exam Guide, 6th Edition, McGraw-Hill, New York, 2013, pp. 62, 1112, 1115-
1116, 1120-1122, 1192
http://en.wikipedia.org/wiki/Capability_Maturity_Model