1. 1 System Development Life Cycle (SDLC) A series of steps completed over a period of time by analysts in the course of a system development or maintenance project. The main steps of the SDLC include - Analyzing how the current system meets users’ information needs - Providing a design for a new system or a modification of an existing system to meet these needs - Developing a system based on the design - Implementing the system - Maintenance

2. 2 System Development Life Cycle Phase 1 : Preliminary Investigation Phase 2 : System Analysis Phase 3 : System Design Phase 4 : System Development Phase 5 : System Implementation and evaluation

3. 3 Phase 1 Preliminar y Investigati on Phase 2 System s Analysi s Phase 3 Systems Design Phase 4 Systems Developm ent Phase 5 Systems Implementati on and Evaluation Systems Request Prelimi nary Investi gation Report System Require ments Docume nt System Design Specific ation Complete Functioni ng IS Operatio nal IS STO P Replac e IS Waterfall model of SDLC STO P = Terminate Development

4. 4 Phase 1 : Preliminary Investigation (Feasibility Study) A written request from management or an end user triggers the start of the systems development life cycle. This written request is called a system request. The purpose of the preliminary investigation phase is to identify clearly the nature and scope of the problems mentioned in the systems request. Because identifying the problem is the focus of the preliminary investigation, this phase is sometimes called the problem definition phase.

5. 5 Phase 2 : System Analysis The purpose of the systems analysis phase is to learn exactly what takes place in the current system, to determine and fully document in detail what should take place, and to make recommendations to management on the alternative solutions and their costs. Through the process of fact-finding or requirements determination, You first define all the functions performed by the current information system. At the same time, you determine what modifications are needed by the organization in the improved version of the information system.

6. 6 The end product you create for this life cycle phase is the system requirements document, which documents all end user and management requirements, all alternative plans and their costs, and your recommendations to management. After you present your results from this phase to management, management decides on the best alternative.

7. 7 Phase 3 : System Design The purpose of the systems design phase is to determine how to construct the information system to best satisfy the documented requirements. You must design all required information system outputs, files, inputs, application software programs, and manual procedures. Also, you must design the internal and external controls, which are computer-based and manual steps that guarantee the information system will be reliable, accurate, and secure.

8. 8 The design is documented in the system design specification and is presented to the management and the end users for their review and approval. Management and end user involvement is critical so there is no misunderstanding about what the IS is to do, how it will do it, and what it will cost, After all systems design steps have been completed and if the developments is not terminated, you then enter the next phase, system development.

9. 9 Phase 4 : System development System development is the phase during which the information system is actually constructed: application programs are written, tested, and documented; operational documentation and procedures are completed; and end user and management review and approval is obtained. The end product of this phase is a completely functioning and documented information system. As is true with all other phases, the system development phase ends after management has reviewed and approved all results of the phase.

10. 10 Phase 5 : System implementation and evaluation After the system development phase is completed, you then proceed to systems implementation. Activities for this phase include conversion of data to the new system’s files, final training of the end users, and the transition from the old system to the new system. It is at this point that the end users and management actually begin to use the constructed IS. As part of a complete systems development life cycle, provision is made to allow for post- implementation systems evaluation at regular intervals.

11. 11 The purpose of these evaluations is to determine if the information system operates as proposed, and if the costs and benefits are as anticipated. After the SDLC: system operation During the systems operation phase, changes will need to be made to the information system. These changes are classified as either maintenance or enhancements. Maintenance changes are made to correct errors or to conform with government requirements. Enhancements are modifications that add or change capability within the system. Adding new information to an existing printed report and the addition of new report are examples of enhancements.

12. 12 7 Implemen ting and evaluating the system 1 Identifying problems,o pportunities, and objectives 2 Determining information requirement s 3 Analyzing system needs 4 Designing the recommen ded system 5 Developin g and documenti ng software 6 Testing and maintainin g the system

13. 13 Syste ms plan ning Syste ms analy sis Syste ms desig n Systems implemen tation Syste ms supp ort Obsolete system New, related problem or requirement New implementation alternative or requirement Impleme ntation error (bug)

14. 14 The PIECES Framework by James Wetherbe P The need to improve performance. I The need to improve Information(or data). E The need to improve economics or control costs. C The need to improve control and security. E The need to improve efficiency of people and machines. S The need to improve service to customers, partners, employees, and so on.