SYSTEMS ANALYSIS AND DESIGN

Systems Analysis and Design

Systems Analysis and Design

System Development Lifecycle Models

The first stage is named as Preliminary/Feasibility Study. In this stage, the actual problem is identifiedwhich is the most important and sensitive task to be diagnosed. In this stage, analyst takes a lot of time to measure and identify where the problem exists in the system. Problems are analysed in different dimensions and then analyst come up with an appropriate decision regarding the actual problem. The second stage is called Systems Analysis. The third stage is named as System Design. It is the designing phase where analyst drafts a lot of rough designs on the computer and checks whether the system includes all the requirements or not. The appropriate design is then selected and implemented for the system development. The fourth stage is Software Development. The fifth stage is called System Testing. In this section, systems are tested and here analyst looks for the expected outcomes Cockburn, 2001: 144-149). If desired results are not coming then the analyst adjust the problem accordingly. The sixth stage is a System Implementation stage. The final stage is called Evaluation/Review. In this stage the analyst evaluates whether the system is performing with reference to the customer requirements that were initially identified. Additionally the final cost of the system compared to its original budget. The most important part of all the stages being discussed in the SDLC is the monitoring of the system. Continuous monitoring is required even if the the system is properly working. At some point later, adjustments may be required in the system as the desired results no longer satisfy the requirement.

Waterfall model

The traditional Waterfall Life Cycle has been used for many years. In this model a software is developed in a downward style just like a waterfall. This model is divided in to phases. As one phase executed completely, the system jumps to the next phase and start processing the requirements of the specified one. Therefore, it can be said that this model is not flexible. Time and cost measurements are not easy to diagnose in this model. This model is quite familiar among the analysts therefore it can be easily developed within short span of time.

Spiral model

This model is a reflection of prototyping and the waterfall model. A lot of features of these models are embedded in spiral model. The spiral model is specifically ideal for huge and costly projects. This model is much more focused towards the risk-driven approach and analyses different risk areas of the projects. For e.g. the costs, adjustments in the requirements etc. Therefore, it can be said that this model presents the concept of minimizing risks unlike the other models specially waterfall. As the name suggests, this model works in a spiral (outward) fashion. The work is started from the centre point of the spiral. This model is very much flexible, as on the completion of each loop, the work is evaluated by the clients and adjustments (if any) are done ...