Software Quality

By Raul Bernardino

Introduction:

The quality of the software is hard to define the clear definition. The Software Quality is a relative means to the people that is not involving directly in the process of the construction. The quality of any products and services can be measured, however the measurement are only an indicative to guide the managers. “The high quality means that, it is fitting the purposes in which the quality of the software satisfying the needs and expectation of the stakeholders and it is not cause a damage to them. The external quality processes are needed in order to improve the overall quality enhancement and it also creates secondary complimentary views on the system that embodied in the implementation,” Hall, P. A.V. & Fernandez-Ramil, J. (2007, p.363).

There are three factors that are involving in the process of contracting a software application in order to reach the sets standards. They are as follows:

The internal factor such as the software system application has to be maintained, the application is constructed in the modular, the application performance is testable, the application can be reused, the application is adjustable, the application is interoperable, and system application is readable and understandable.

The process factor such as the software system application is able to improve, able to track the system, the system application is effective, the process application is able to predict, the system application is able to maintain, and the system application is repeatable.

The external factor such looking that the functionality of the system application, the efficiency of the application compare to the other system, the system application is reliable, adaptable and robust, the system application is having an accuracy, the system application is able to use, and the application software is able to conform. According to the Phillips (2005): the conceptual model of the software quality dimensions, as it shows in the below diagram:

In the business context, the software qualities are defined in two related concept such as:

a)     The functional quality which is the system application is reflecting to design, conform to the requirements, and it is including fitting the purposes and it is also comparable to the competitor’s application products. The functional qualities are measured during testing period.

b)    The structural quality which is referring to the non functional requirements that support the functionality such as it is able to maintain, the system is robust, it has high degree of how it product correctly. Usual the structural qualities are evaluated via  deep analysis on software structure, the source code, and how it designs or architecting

The quality measurement can be found in the number of the line of the code (N), number of comments in the code (C), and number of the complexity in the coding (X).  The formula is “Q = w_n*N+w_c*C+w_x*X,” Hall, P. A.V. & Fernandez-Ramil, J. (2007, p.343), whereas the w is the weight value that we need to determine. For instance we three different programming experts to weight the value, it is good to have many experts in weight the values and take the average.

Although many advance technology, the software development still in the complex of the intellectual activities, therefore it can be measured as the quality culture. The implication is that, different people have different views of measuring any product qualities; therefore it is relative compare to one and another. The important knows that, people as a central of the process and an important resource for software organization such as knowledge, an experience, and understanding of the execution of the software application, which is processing the iteration whereas to provide the inputs to the new iterations. An organization that has quality culture when the qualities is highly valued and when the managers are supporting the employees who care for less tangible aspect of the qualities; as a result everyone in the organization feels ownership of the product and responsible for archiving the possible quality within the available resources.

The quality economics: According to the Feigenbaum, A. and Juran, J., in years 50s and 51s, both promoted the concept of quality economics in quality control. Feigenbaum, A. approach was all cost that associated with the quality, both those cost associated with the quality improvement and cost for extra work with quality failure. He identified three classes of cost such as: prevention cost, appraisal cost, and future cost.

In conclusion: The quality of any products and services are able to measure with three factors such as internal factor, external factor, and process factor. People are a central of the process and important resources for the software development.

References:

Hall, P. A.V. & Fernandez-Ramil, J. (2007) Managing the Software Enterprise:

Software Engineering and Information Systems in Context. London: Thomson Learning.

Lecture notes, MNGSWE_WK8_seminar

Sommerville, I. (2004). Software engineering 7^th ed. Essex, England: Pearson

Education Limited.

Sommerville, I., (2001), Software documentation, [Online]. Available from:

http://www.literateprogramming.com/documentation.pdf (Accessed: 24 November 2011)

Software Quality,[Online]. Available from:  

http://en.wikipedia.org/wiki/Software_quality (Accessed: 24 November 2011)