Background Research

System Design Methodologies

In order to attain some sense of how to approach and manage such a project, a structured methodology is required.

Types of methodologies

The stages a project goes through are formulised in the traditional systems development life cycle (SDLC).

• Feasibility study, which investigates the possibility of carrying out the project given the available
  resources the company has.
• System investigation, which explores the system as a whole.
• Systems analysis, which determines the requirements of the new system.
• Systems design, which produces detailed plans and specifications of the new system.
• Implementation, which is focused on building the system.
• Review and maintenance, which evaluates the system, identifies problems in the new system and
  fixes them.
  

There are many methodologies within the SDLC that focus on different areas within the life cycle. The types of methodologies that will be discussed are:

• Structured systems analysis and design method (SSADM)
• The waterfall model
• Prototyping

Structured systems analysis and design method (SSADM)

SSADM has seven stages as illustrated below:

• Feasibility study
• Investigation of current environment
• Business system options
• Definition of requirements
• Technical system options
• Logical design
• Physical design

This methodology is applicable for teams as it relies on the skills of key personnel being available. The heavily structured format of SSADM indicates that it is generally used for large-scale development projects and requires much documentation. A disadvantage of this methodology is that maintenance is not included within it. This can cause problems in the long-term if any problems occur in the system.