Information System Development Life Cycle Models - High Level Models and Methodologies for Information Systems - page 21

it is possible to ascertain that there are key components that all congruent frame-
works must necessarily entail. The most notable one is the segmentation of the
development process into phases, with each phase having a beginning, an end, a
series of speci

c activities, deliverables (documentation that is prepared regularly to
ensure performance accountability for each required task), and monitoring tools.
Cohen ( 2010 ) notes that this same principle is also true for the introduction of IS
not through their development in house, but through external acquisition (the
purchase of a set of software applications from an external vendor). Both imply a
process of implementation, maturing, and termination.
The core objective of the development or implementation of a system is its

ef cient integration in real-life situations. Therefore, two of the primordial steps in

the life cycle are the assessment of what the different people involved in the
system

s use will require and a knowledge of the context in which the system will
be operated. The negligence of these two essential elements is at the origin of
several issues in systems

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use in real settings (Tetlay and John 2009 ). The usability
aspect of a system is central, that is why the inclusion of the user in the entirety of
the development life cycle is crucial. For developers, it is paramount to have all the
correct information regarding the users

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needs. Misinformation has repercussions
on the development of the system, and it usually results in the implementation of
products that fall short of the users

'

expectations and have a diminished produc-
tivity. It is important to potentiate the users ' participation, namely by informing
them about how the development process works and the need for accurate infor-
mation (Durrani and Qureshi 2012 ).
However, even considering these crucial common points that all frameworks
must necessarily include, the methodology for system development has a great
variety of approaches, which we call models of system development life cycle
(SDLC). Some of the most commonly cited are the spiral, waterfall, V-shaped, and
agile models. Given the multiplicity of research studies on this field, it is crucial to

outline an overview of them, to help further understand which one of them would
be more appropriate for a speci c project. The point where the model or framework

that will guide the development process is chosen is a central strategic aspect that
will undeniably have an impact on the effectiveness of the system in the long run.
The wrong life cycle can delay the project and affect client satisfaction, and it can
even mean the cancelation of the system (Executive Brief 2008 ).
In this paper, we will offer a panoramic overview of the most signi cant models

of SDLC, which will present a useful tool for the embryonic stages of any IS
development process.

2.2 The Waterfall Model

The waterfall model was introduced by Royce in ( 1970 ), speci cally in the context

of spacecraft mission software design, and is one of the most popular methods of
assessing the evolution of a product or system. Essentially, it is a step-by-step