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System development And Life Cycle- Recognition of need And Feasibility

 System Development And Life Cycle 



An effective System Development Life Cycle (SDLC) should result in a high quality system that meets customer expectations, reaches completion within time and cost evaluations, and works effectively and efficiently in the current and planned Information Technology infrastructure.
  • Recognition of Need 
Key Question: What is the problem or opportunity?
Stage: Preliminary survey / initial investigation
Result: Statement of scope and objectives performance criteria.

• Analyst must know what the problem is before it can be solved.
• The basic for system development is to recognize of need to improve or develop an information system or a procedure.
• This need leads to a preliminary survey or an initial investigation to determine that alternative system can solve the problem.
• It includes looking into duplication of effort, bottlenecks, inefficient existing procedures or weather parts of existing system would be candidates for computerization.
• If  problem is serious management want to have an analyst.
• First task of analyst is to specify the scope and objective of the problem.

  • Feasibility Study
Key Question: What are the user demonstrable needs? Is the problem solving? How can the problem be redefined?
Stage: Evaluation of existing system and procedures, analysis of alternative candidate system, cost estimates.
Result: Technical feasibility, cost / benefit analysis, system scope and objectives, statement of new scope and objectives. 

• Feasibility study is a test of a system proposal according to its workability, impact on the organization, ability to meet user needs, and effective use of resources.
• Focuses on 3 major questions:
  1. What are user's demonstrable needs and how does a candidate system meet them?
  2. What resources are available for given candidate system? Is problem worth solving?
  3. What are the likely impact of the candidate system on the organization? How well does it fit within the organization's master MIS plan?
• Feasibility study is not to solve problem but to acquire sense of its scope.
• In this study aspects of problem to be included in system are determined.
• Cost and benefits are estimated with great accuracy at this stage.
• This is for detailing the nature and scope of the proposed system.
• This is crucial / important point in life cycle.
• Changes in proposal are made in writing, depending on the complexity, size and cost of the project.
• The changes should be verified before committing the project to design.
If you are interested to know more on any other subject in which you are interested or if you have any doubts then tell us in comment about it.  








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