LITERATURE REVIE

Literature Review



Literature Review

1. Management Report

The Structured Systems Analysis and Design Methodology (SSADM) has been developed and mainly used by government departments. This is why it is mainly designed for large-scale Information Systems with high volume business events. SSADM specifies exactly the flows and tasks of a development project and produces a detailed documentation of the project. SSADM sticks to the traditional waterfall model, which allows review of each stage but requires its accomplishment before the next one can begin. SSADM focuses on the Analysis and Design stages of the Systems Development Life Cycle (SDLC). SSADM combines three methods, complementing each other within a systems development cycle: Logical Data Modelling, Data Flow Modelling, Entity Event Modelling.

Its main benefits are: Improvement of quality, detailed documentation of the development stages, and reusability for similar projects that follow. But these points are not likely to be taken into consideration in practice. This is due to the danger of over-analysing, which can be very time and -cost consuming. Delays caused by SSADM can vary in range from months to years. Especially for small or medium-sized companies, huge delays can lead to serious financial and resource problems. So, it is highly advisable to investigate alternative methods, such as the Rapid Application Development (RAD) or to use an off-the-shelf product, which is much less expensive and less time-consuming and has already been tested by various other companies.

2. Introduction

In the late seventies, large-scale Information Systems (IS) became popular in order to manage large systems for billing, salaries, stock control and other applications requiring huge databases. Many organisations did not have an appropriate development method. First of all, analysis of the systems requirements was carried out on an ad hoc basis, so often the final product did not exactly meet the business requirements. Time consuming 3GL programming languages, such as Cobol, were used and the produced files and databases were inflexible.

3. Discussion of SSADM

3.1. Benefits of SSADM

Timelines: Theoretically, SSADM allows one to plan, manage and control a project well. These points are essential to deliver the product on time.

Usability: Within SSADM special emphasis is put on the analysis of user needs. Simultaneously, the systems model is developed and a comprehensive demand analysis is carried out. Both are tried to see if they are well suited to each other.6

Respond to changes in the business environment: As in SSADM documentation of the project's progress is taken very seriously, issues like business objectives and business needs are considered while the project is being developed. This offers the possibility to tailor the planning of the project to the actual requirements of the business.

Effective use of skills: SSADM does not require very special skills and can easily be taught to the staff. Normally, common modelling and diagramming tools are used. Commercial CASE tools are also offered in order to be able to set up SSADM easily.

Better quality: SSADM reduces the error rate of IS by defining a certain quality level in the beginning and constantly checking the ...