Modern Systems Analysis
and Design
        Fourth Edition
      Jeffrey A. Hoffer
       Joey F. George
     Joseph S. Valacich
       Chapter 1
The Systems Development
      Environment
         © 2005 by Prentice Hall
              Learning Objectives
       Define information systems analysis and design.
       Describe the different types of information systems.
       Describe the information 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).
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                    Introduction
      Information Systems Analysis and Design
         Complex organizational process whereby
          computer-based information systems are
          developed and maintained
      Application Software
         Computer software designed to support
          organizational functions or processes
      Systems Analyst
         Organizational role most responsible for analysis
          and design of information systems
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      Introduction (cont.)
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      A Modern Approach to Systems
          Analysis and Design
       1950s: focus on efficient automation of existing
       processes
       1960s: advent of 3GL, faster and more reliable
       computers
       1970s: system development becomes more like an
       engineering discipline
       1980s: major breakthrough with 4GL, CASE tools,
       object oriented methods
       1990s: focus on system integration, GUI applications,
       client/server platforms, Internet
       The new century: Web application development,
       wireless PDAs, component-based applications
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      Types of Information Systems
       and Systems Development
      Transaction Processing Systems (TPS)
          Automate handling of data about business activities
           (transactions)
          Process orientation
      Management Information Systems (MIS)
          Converts raw data from transaction processing system into
           meaningful form
          Data orientation
      Decision Support Systems (DSS)
          Designed to help decision makers
          Provides interactive environment for decision making
          Involves data warehouses, executive information systems (EIS)
          Database, model base, user dialogue
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        Types of Information Systems
      and Systems Development (cont.)
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          Developing Information
          Systems and the SDLC
      System Development Methodology
         Standard process followed in an
          organization
         Consists of:
            Analysis
            Design
            Implementation
            Maintenance
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      Systems Development Life
           Cycle (SDLC)
      Traditional methodology for developing,
      maintaining, and replacing information
      systems
      Phases in SDLC:
         Planning
         Analysis
         Design
         Implementation
         Maintenance
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   Standard and Evolutionary Views
              of SDLC
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              SDLC Planning Phase
       Identify, analyze,
       prioritize, and
       arrange IS needs
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              SDLC Analysis Phase
       Study and
       structure system
       requirements
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               SDLC Design Phase
                                                      Logical design:
       Convert                                        functional features
       recommended                                    described
       solution to system                             independently of
                                                      computer platform
       specifications
                                                       Physical design:
                                                       logical
                                                       specifications
                                                       transformed to
                                                       technology-
                                                       specific details
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       SDLC Implementation Phase
       Code, test, install,
       and support the
       information system
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         SDLC Maintenance Phase
       Systematically
       repair and
       improve the
       information
       system
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          The Heart of the Systems
           Development Process
       Current practice combines analysis, design, and implementation
       into a single iterative and parallel process of activities
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       Traditional Waterfall SDLC
                                           One phase begins
                                           when another
                                           completes, little
                                           backtracking and
                                           looping
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         Problems with Waterfall
               Approach
       System requirements “locked in” after
       being determined (can't change)
       Limited user involvement (only in
       requirements phase)
       Too much focus on milestone deadlines
       of SDLC phases to the detriment of
       sound development practices
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        Alternatives to Traditional
             Waterfall SDLC
       Prototyping
       CASE tools
       Joint Application Design (JAD)
       Rapid Application Development (RAD)
       Agile Methodologies
       eXtreme Programming
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                              Prototyping
       Iterative development process:
       Requirements quickly converted to a working system
       System is continually revised
       Close collaboration between users and analysts
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               CASE Tools
       Computer-Aided Software Engineering
       Software tools providing automated
       support for systems development
       Project dictionary/workbook: system
       description and specifications
       Diagramming tools
       Example products: Oracle Designer,
       Rational Rose
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   Joint Application Design (JAD)
       Structured process involving users,
       analysts, and managers
       Several-day intensive workgroup
       sessions
       Purpose: to specify or review system
       requirements
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       Rapid Application Development
                   (RAD)
       Methodology to decrease design and implementation time
       Involves: prototyping, JAD, CASE tools, and code
       generators
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             Agile Methodologies
       Motivated by recognition of software
       development as fluid, unpredictable,
       and dynamic
       Three key principles
          Adaptive rather than predictive
          Emphasize people rather than roles
          Self-adaptive processes
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           eXtreme Programming
       Short, incremental development cycles
       Automated tests
       Two-person programming teams
       Coding and testing operate together
       Advantages:
          Communication between developers
          High level of productivity
          High-quality code
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       Object-Oriented Analysis and
                  Design
       Based on objects rather than data or
       processes
       Object: a structure encapsulating attributes
       and behaviors of a real-world entity
       Object class: a logical grouping of objects
       sharing the same attributes and behaviors
       Inheritance: hierarchical arrangement of
       classes enable subclasses to inherit
       properties of superclasses
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       Rational Unified Process (RUP) involves an iterative,
       incremental approach to systems development
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                       Summary
       In this chapter you learned how to:
         Define information systems analysis and design.
         Describe the different types of information
           systems.
         Describe the information 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).
1-29                       © 2005 by Prentice Hall