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Systems Development Environment. Chapter 1 Modern Systems Analysis & Design. Chapter 1 Learning Objectives. Define information systems analysis and design Describe different types of information systems Describe Systems Development Life Cycle (SDLC)
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Systems Development Environment Chapter 1 Modern Systems Analysis & Design
Chapter 1 Learning Objectives • Define information systems analysis and design • Describe different types of information systems • Describe Systems Development Life Cycle (SDLC) • Explain Rapid Application Development (RAD), prototyping, Joint Application Development (JAD), and Computer Aided Software Engineering (CASE) • Describe agile methodologies and eXtreme programming • Explain Object Oriented Analysis and Design and the Rational Unified Process (RUP)
Today’s Agenda • What is SA&D? • What Does a Systems Analyst Do? • Skills • Participants in Systems Development • What Goes Wrong • Systems Development Methodology • What is a Methodology • For What Types of Systems is a Methodology Used? • Traditional Systems Development Process (SDLC) • Other Methodologies
Information Systems Analysis and Design The complexorganizational process whereby computer-based information systems are developed and maintained.
What Does a Systems Analyst Do? • Studies the problems, needs, and opportunities of an organization • Determines how people, methods, “computer technology,” and organizational methods can work together to best improve the business • Responsible for developing efficient methods for capture, movement, processing, and storage of data • Bridges technology and organization • Central member of team (of various stakeholders)
What Skills Does an Analyst Need?A Starter Set • Analytical skills • Systems thinking • Understanding business/organization via general and firm-specific knowledge • Identifying problems/opportunities • Analyzing and solving problems/opportunities
Inputs Outputs Process Storage More Systems Thinking:O = f(I,P,S) Model of a System
C1 C4 C2 C5 C3 C6 C4 C1 C5 C2 C6 C3 More Systems Thinking: Design/Reengineering • System simplification concepts: • Which system is more • Cohesive • Decoupled System A: System B:
What Is Systems Thinking? • Looking at a situation as a system of interacting components • abstracting, decomposing • Identifying problem and designing selecting, implementing a solution • simplifying, reengineering internals of (i.e., processes) and interactions between components – including interfaces, using cohesion, decoupling
What Skills Does an Analyst Need?A More Complete Set • Analytical skills • Systems thinking • Understanding business/organization via general and firm-specific knowledge • Identifying problems/opportunities • Analyzing and solving problems/opportunities • Technical skills • Structuring requirements • Designing databases, forms, reports, navigational interfaces • Management skills • Resource management • Project management • Risk management • Change management • Interpersonal skills • Communicating • Working in teams • Facilitating groups • Managing expectations
Who Are the Players in Systems Development? • User(s) • Business manager(s) • Steering committee • Application programmers • System programmers • Database, network, and other technology specialists • Security / auditing staff • Human factors experts • Documentation specialists
Analyst as a Member of System Development Team Comment on / think about: What differentiates high performing teams from less successful ones?
What Goes Wrong in General when Applying Skills in an Organization? 12. Too long 11. Inability to change business processes 10. Not allowing out-dated system components to be replaced 9. Excessive spending on “maintenance” 8. Functions delivered are out-of-date 7. Inadequate technology impedes rapid response to market 6. Users lose patience, but “home grown” solutions out-of-control 5. Critical data locked inside inaccessible systems 4. IS development priorities not consistent with business priorities 3. IS staff does not understand business or its needs 2. Management does not understand IS 1. IS unplanned or misdirected
Systems Development Methodology A standard process followed in an organization to conduct all the steps necessary to analyze, design, implement, and maintain information systems
Methodology, Technique, Tool • Methodology • Overall approach, usually within a framework or architecture • Technique • A way to do a specific task (e.g., interview, ERD, DFD, use-case diagram) • Often graphical • Tool • An aid which helps to complete a technique (e.g., Visio, PowerPoint, MS-Project) or manage data used across techniques
CASE: Examples of Tools • Case tools • Software tools that provide automated support for some portion of the systems development process • Examples of tools/functions supported • Diagramming • Generating screens and reports
What Is Analyzed Via Methodology? • Data (input/capture and storage) • Information (output/presentation) • Data flow (movement/transfer) • Processing logic (manipulation/analysis) Note: These can be viewed as related but separate systems!
Types of Information Systems • Transaction processing • MIS • Business Intelligence • DSS (Individual & Group) • ESS/EIS • Expert System Note: See Table 1-1 for differences • characteristics • development orientation (e.g., process or data)
Traditional Systems Development Methodology: Systems Development Life Cycle (SDLC) Chapters 4-5 Chapters 6-9 Chapter 16 Chapter 15 Chapters 10-14
SDLC Planning Phase Identify, analyze, prioritize, and arrange IS needs
SDLC Analysis Phase Study and structure system requirements
SDLC Design Phase Logical design: functional features described independently of computer platform Convert recommended solution to system specifications Physical design: logical specifications transformed to technology-specific details
SDLC Implementation Phase Code, test, install, and support the information system
SDLC Maintenance Phase Systematically repair and improve the information system
Iterative/Agile Development • Repetition of refining steps • Successively closer to goal • Evolutionary/adaptive • Continuous, self-adapting change • simpler state to more complex or better state • Focus on people not roles (people are talented and creative, not replaceable parts) – see Table 1-4
Spiral Development Design High-level Requirements Analysis Detailed Requirements Customer Review
Figure 1-11: Prototyping: A Methodology or Component of Other Methodologies
How Do Methodologies Change? Some Trends • Move from “art” -> “science” (tension) • In-house development • Outsourcing • Purchased applications • Modularized • Web orientation
In Summary • What is systems analysis and design? • What does a systems analyst do? • What is a systems development methodology? • Why use one?