 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | |
| By N2H | ||||||||||||||||||||||
System development methodology
August 4, 2008
If you're new here, you may want to subscribe to my RSS feed. Thanks for visiting and have a nice day!
“A methodology” is a recommended collection of philosophies, procedures, rules, techniques, phases, tools, documentation, management and training for developers of IS.
Objectives of Methodology
-
To capture, record and document accurately, the user needs.
-
To monitor the project and report on progress (project management ability)
-
To facilitate the development of quality system within the set time and set budget
-
To facilitate proper documentation of both project process and the project deliverables, assisting in future maintenance.
-
To facilitate at an early stage the mechanics of change control.
-
To facilitate the delivery of system that are liked by the end user.
-
Complete coverage of all the development activities involved in system development.
-
Simplicity: The tools, techniques e.t.c. should be easy to use.
-
Validation of the designs:- the methodology should conclude a mechanism for reviewing its own results.
-
Separation of analysis from design, there should be distinct focus on user need, quite separate from implementation needs.
A methodology can be said to have various features. These features can be categorized into technical model and managerial model.
A methodology needs to have a technical model. This model includes features like the tools, tools which will help the developers in the process of developing an Information System. These tools help in every phase or sub phase involved in the methodology. e.g. CASE tools, project management tools, Drawing tools , Data dictionary e.t.c.
A methodology also needs to have a technique. A methodology can have many techniques, Techniques helps to verify and expound on the methodology, thus they enable the phase and subphase of methodology to be carried out according to the methodology’s principle.
Technique act as guides of methodology’s phase. Technique address different parts (phases) of a methodology.
Techniques also enable easy understanding of what the methodology requires e.g. root pictures, conceptual model, DFD, Decision trees/tables, Entity Life Cycle, Structured diagrams, normalization e.t.c.
A methodology also needs to have a philosophy, in that it needs to have the underlying theories and assumptions that the authors of the methodology believes in. This feature helps to shape and guide the development of an Information System. It also enable the understanding of the methodology.
A methodology also has a managerial model that has a feature of a methodology. This feature is that of the development structure, in that a methodology needs to have a development structure that;
-
Identifies the phases, subphases, steps and tasks to be done in the methodology.
-
Identifies the outputs to be produced and under which circumstances they should be produced.
-
Constraints to be applied and people to be involved. This feature provides for the development process to be really managed and controlled.
Initially in the early 60s there was no appreciation for a methodology. Application systems were developed without the aid of an explicit Information System development methodology.
Also there was a growing appreciation of analysis and design parts of the system development and therefore the role there was increased demand for the role of an analyst and programmer.
There was also a realization that as organization grow in size and complexity. It was desirable to move away from one-off solution to a more integrated Information System.
There was also appreciation of an accepted methodology for the development of an I.S.
What is the rationale for writing a methodology
The rationale for writing a methodology are:
The methodology should improve the end product of a development process i.e. a better I.S.
A better development process: In that the methodology should provide improved management and project control so that the organization can gain from the benefits that accrue from a tightly controlled development process.
Selecting/Adopting
Theoretically speaking, the best methodology is the one that is best suited to the project work at hand. In practice, the best methodology may be the one that the designer understands well.
In some cases, the right methodology is the one that has been recommended within the organization’s standards.
Common Approaches
Adhoc: No formal recognition is given to methodologies
Contingency Approach: We use different methodologies, depending on the nature of the project.
Prototyping / Evolutionary Development: We use it in those context where the user needs are unclear, the business area is unfamiliar, the level of risk is high e.t.c.
Adavantages of a methodology
-
Increased user involvement translating to a more likeable system.
-
Prototyping has the inherent capacity for accommodating risks.
-
Quicker systems Development.
-
Superior User Interface.
-
Missing functions/features can be detected early.
Disadvantages of a methodology
-
Poor documentation.
-
Confusion between the prototype and the real system.
-
Project Management is difficult.
-
It is difficult to draw up a prototype contract.
-
As a consequence of poor documentation system maintenance may be difficult.
Comments
Got something to say?
You must be logged in to post a comment.
Powered by FireStats