IS Development Methodology Hele.Mai Haav: CSC230-Spring 2003 IS Development Methodology

Objectives: Describe each of the steps of IS development cycle Explain the usage of computer aided systems engineering in the process of IS development Use the systems development cycle, and a model of information systems components as problem-solving frameworks to help you to propose IS solutions to simple business problems (Term project)

Developing IS Solutions systems approach applied to the development of IS solutions to business problems It is a major responsibility of today’s managers.

The Systems Development Cycle 1. Investigations 2. Analysis 3. Design 4. Implementation 5. Maintenance

Systems Investigation Do we have a business problem? What is causing the problem? Would a new IS help solve the problem? What would be a feasible IS solution to our problem?

Feasibility studies is a preliminary study to investigate the information needs of users and determine the resource requirements, costs, benefits, and feasibility of a proposed project.

Organizational feasibility How well the proposed system supports the strategic objectives of the organization Technical feasibility Hardware and software capability, reliability, and availability. Economic Feasibility Cost savings, increased revenue and profits, decreased investments Operational feasibility End-user acceptance, management support, customer, supplier and government requirements

Cost analysis - a part of feasibility studies Tangible costs: costs of hardware, software, employee salaries, etc. Intangible costs: difficult to quantify, for example, the loss of customers goodwill caused by disruptions arising from the installation of a new system

Benefit analysis Tangible benefits like increase in sales or profit, decrease in information processing costs, increased operational ability and efficiency, etc. Intangible benefits: improved customer service and management decision making, improved business and community image, improved competitive position, etc.

The result of feasibility study is a report which includes preliminary specifications and a developmental plan for the proposed system. If management of the firm approves the recommendations of the feasibility study, the system analysis stage can start.

Systems Analysis describes what a system should do to meet the information needs of users It is detailed study of the information needs of the organization and end users the activities, resources, and products of any present IS the IS capabilities required to meet your information needs, and those of other end users RESULT Functional Requirements

Systems Design specifies how the system will accomplish the objective described on system analysis stage Systems design can be viewed as the design of user interfaces (screen, form, report, and dialog design data (data structure design) process (program and procedure design)

Systems Design RESULT system specification satisfying the functional requirements developed in the systems analysis stage

System specification User interface specification Database specification Software specification Hardware and facilities specification Personal specifications

Systems Implementation and Maintenance Systems Implementation involves hardware and software acquisition, software development, testing of programs and procedures, development of documentation, and systems installation.

Systems Implementation and Maintenance Systems Maintenance involves the monitoring, evaluating, and modifying of a system to make necessary improvements.