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Systems Development Life Cycle. Overview and Feasibility studies. Introduction. The application of a systems approach to the development of information systems solutions to business problems is called ’Information Systems Development’
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Systems Development Life Cycle Overview and Feasibility studies
Introduction • The application of a systems approach to the development of information systems solutions to business problems is called ’Information Systems Development’ • When applying this process in this way, a multistep process or cycle emerges • This cycle is known as the SDLC
Systems Development Life Cycle Systems Investigation Product: Feasibility Study Systems Analysis Product: Functional Requirements Systems Design Product: Systems Spec Systems Implementation Product: Operational System Systems Maintenance Product: Improved System
Systems Investigation • Do we have a business problem/ opportunity • What is causing the problem • Would a new or improved information system solve the problem • What would be a feasible information system solution to our problem • What do we do to achieve a solution
Systems Analysis • Analyse the information needs of; • End users • Organisational environment • Existing information systems • Develop functional requirements of a system that can meet the needs of end users
Systems Design • Develop specifications for; • hardware • software • people • data • information products that will satisfy the functional requirements of the proposed system
Systems Implementation • Acquire or develop hardware and software • Test the system and train people to use it • Convert to the new system
Systems Maintenance • Use a post-implementation review process to; • monitor • evaluate • modify • … the system
Systems Investigation • A Strategic Information Systems plan formulates policies, objectives and strategies for delivering IS and allocating resources • Emphasis on planning a computer based information system that will; • improve business performance • improve competitive performance
Tactical IS Planning • Current and future information requirements are assessed • Requirements sub-divided into project proposals • Projects are evaluated, ranked and fitted into a development plan • Resource allocation plan developed
Operational IS Planning • Preparation of annual operating budgets which specify financial and other resources • Planning of individual IS development projects • The need arises for project planning, control and management
Feasibility Study • Preliminary study to investigate; • information needs of prospective users • determine resource requirements • costs • benefits • Establish feasibility of the project
Feasibility Study - rationale • The process of developing a major information system can be costly • The systems investigation stage uses a feasibility study to verify the need for a proposed project
Methods for information gathering • Interviews with employees, customers and managers • Questionnaires to appropriate end users in the organisation • Personal observation or involvement in business operations • Examination of documentation, reports and procedural manuals
Feasibility report • Findings of the data gathering exercise usually formalised in a written report • It includes; • preliminary spec • developmental plan of proposed system • Submitted for management approval before development can start
Cost Benefit Analysis • Quantified costs and benefits; • costs of hardware/software • employees salaries • Costs and benefits that cannot be quantified • customer goodwill • employee morale
Cost Benefit Analysis • Least cost • Breakeven Analysis • Payback Analysis • Discounted cash flow • Other in-house methods
Least cost • Purchase cost • Lifetime cost Profit Cost