INTRODUCTION. Objectives. Unit 1: Introduction to Systems Analysis and Design. Key Ideas

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1 Objectives Unit 1: Introduction to Systems Analysis and Design Understand the fundamental systems development life cycle and its four phases. Understand the evolution of systems development methodologies. Be familiar with the different roles on the project team. 1/2006 OOAD 1 1/2006 OOAD 2 Key Ideas INTRODUCTION Many failed systems were abandoned because analysts tried to build wonderful systems without understanding the organization. The primarily goal is to create value for the organization. 1/2006 OOAD 3 1/2006 OOAD 4

2 Key Ideas The systems analyst is a key person analyzing the business, identifying opportunities for improvement, and designing information systems to implement these ideas. It is important to understand and develop through practice the skills needed to successfully design and implement new information systems. THE SYSTEMS DEVELOPMENT LIFE CYCLE 1/2006 OOAD 5 1/2006 OOAD 6 Major Attributes of the Lifecycle The project Moves systematically through phases where each phase has a standard set of outputs Produces project deliverables Uses deliverables in implementation Results in actual information system Uses gradual refinement Planning Why build the system? Analysis Project Phases Who, what, when, where will the system be? Design How will the system work? Implementation System delivery 1/2006 OOAD 7 1/2006 OOAD 8

3 Planning Analysis Identifying business value Analyze feasibility Develop work plan Staff the project Control and direct project Analysis ( AS-IS and TO-BE systems) Information gathering Process modeling Data modeling 1/2006 OOAD 9 1/2006 OOAD 10 Design Implementation Architectural design Interface design Database and file design Program design Construction Installation Establish Support plan 1/2006 OOAD 11 1/2006 OOAD 12

4 Processes and Deliverables Process Planning Analysis Product Project Plan System Proposal SYSTEM DEVELOPMENT Methodologies Design Implementation System Specification New System and Maintenance Plan 1/2006 OOAD 13 1/2006 OOAD 14 What Is a Methodology? A Simple Process for Making Lunch A formalized approach or series of steps Writing code without a well-thought-out system request may work for small programs, but rarely works for large ones. 1/2006 OOAD 15 1/2006 OOAD 16

5 Categorizing Methodologies based on their focus Process-centered Methodologies -- utilize process models as the core of the system concept. Data-centered Methodologies -- utilize data models as the core of the system concept. Object-oriented Methodologies -- This methodology attempts to balance the focus between processes and data. Structured Design Projects move methodically from one to the next step Generally, a step is finished before the next one begins 1/2006 OOAD 17 Waterfall Development Method 1/2006 OOAD 18 Pros and Cons of the Waterfall Method Pros Identifies systems requirements long before programming begins Cons Design must be specified on paper before programming begins Long time between system proposal and delivery of new system 1/2006 OOAD 19 1/2006 OOAD 20

6 Parallel Development Rapid Application Development Critical elements CASE tools JAD sessions Fourth generation/visualization programming languages Code generators 1/2006 OOAD 21 Rapid Application Development Categories 1/2006 OOAD 22 Phased Development-based Methodology Phased development A series of versions Prototyping System prototyping Throw-away prototyping Design prototyping 1/2006 OOAD 23 1/2006 OOAD 24

7 How Prototyping Works Throwaway Prototyping 1/2006 OOAD 25 Agile Development Categories Programming-centric methodologies Extreme Programming (XP) 1/2006 OOAD 26 Selecting the Appropriate Methodology Clarity of User Requirements Familiarity with Technology System Complexity System Reliability Short Time Schedules Schedule Visibility 1/2006 OOAD 27 1/2006 OOAD 28

8 Criteria for Selecting a Methodology Project Team Roles and Skills 1/2006 OOAD 29 1/2006 OOAD 30 Information Systems Roles Project Team Roles Business analyst System analyst Infrastructure analyst Change management analyst Project manager 1/2006 OOAD 31 1/2006 OOAD 32

9 Summary -- Part 1 Summary -- Part 2 The Systems Development Lifecycle consists of four stages: Planning, Analysis, Design, and Implementation The major development methodologies: Structured design the waterfall method Parallel development RAD development Prototyping (regular and throwaway) Agile development XP streamline SDLC There are five major team roles: business analyst, systems analyst, infrastructure analyst, change management analyst and project manager. 1/2006 OOAD 33 1/2006 OOAD 34