This chapter introduces modern systems analysis and design. It describes the systems development life cycle (SDLC) process and different methodologies used, such as prototyping, joint application development (JAD), rapid application development (RAD), and agile methodologies. It also covers object-oriented analysis and design (OOAD) and the Rational Unified Process (RUP). The chapter defines key concepts like systems analysts and different types of information systems.

1. Modern Systems Analysis
and Design
Prof. David Gadish
Chapter 1
The Systems Development
Environment

2. Learning Objectives
ü Define information systems analysis and design.
ü Describe the different types of information systems.
ü Describe the information Systems Development Life
Cycle (SDLC).
ü Explain Rapid Application Development (RAD),
prototyping, Joint Application Development (JAD), and
Computer Aided Software Engineering (CASE).
ü Describe agile methodologies and eXtreme
programming.
ü Explain Object Oriented Analysis and Design and the
Rational Unified Process (RUP).
Chapter 1 2

3. Introduction
n Information Systems Analysis and Design
¨ Complex organizational process.
¨ Used to develop and maintain computer­
based information systems.
¨ Used by a team of business and systems
professionals.
Chapter 1 3

4. Introduction (Cont.)
Figure 1­1 An organizational approach to systems analysis and
design is driven by methodologies, techniques, and tools
Chapter 1 4

5. A Modern Approach to Systems
Analysis and Design
n 1950s: focus on efficient automation of
existing processes
n 1960s: advent of 3GL, faster and more
reliable computers
n 1970s: system development becomes
more like an engineering discipline
Chapter 1 5

6. A Modern Approach to Systems
Analysis and Design (Cont.)
n 1980s: major breakthrough with 4GL,
CASE tools, object oriented methods
n 1990s: focus on system integration, GUI
applications, client/server platforms,
Internet
n The new century: Web application
development, wireless PDAs, component­
based applications
Chapter 1 6

7. A Modern Approach to Systems
Analysis and Design (Cont.)
n Application Software
¨ Computer software designed to support
organizational functions or processes.
n Systems Analyst
¨ Organizational role most responsible for
analysis and design of information systems.
Chapter 1 7

8. A Modern Approach to Systems
Analysis and Design (Cont.)
Chapter 1 8

9. Types of Information Systems
and Systems Development
n Transaction Processing Systems (TPS)
¨ Automate handling of data about business
activities (transactions)
¨ Process orientation
n Management Information Systems (MIS)
¨ Converts raw data from transaction
processing system into meaningful form
¨ Data orientation
Chapter 1 9

10. Types of Information Systems
and Systems Development (Cont.)
n 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
Chapter 1 10

11. Summary of Information
Systems Types
Chapter 1 11

12. Developing Information Systems
n System Development Methodology is a
standard process followed in an
organization to conduct all the steps
necessary to analyze, design, implement,
and maintain information systems.
Chapter 1 12

13. Systems Development Life
Cycle (SDLC)
n Traditional methodology used to develop,
maintain, and replace information systems.
n Phases in SDLC:
¨ Planning
¨ Analysis
¨ Design
¨ Implementation
¨ Maintenance
Chapter 1 13

14. Standard and Evolutionary Views
of SDLC
Chapter 1 14

15. Systems Development Life Cycle
(SDLC) (Cont.)
n Planning – an organization’s total
information system needs are identified,
analyzed, prioritized, and arranged.
n Analysis – system requirements are
studied and structured.
Chapter 1 15

16. Systems Development Life Cycle
(SDLC) (Cont.)
n Design – a description of the
recommended solution is converted into
logical and then physical system
specifications.
n Logical design – all functional features of
the system chosen for development in
analysis are described independently of
any computer platform.
Chapter 1 16

17. Systems Development Life Cycle
(SDLC) (Cont.)
n Physical design – the logical
specifications of the system from logical
design are transformed into the
technology­specific details from which all
programming and system construction can
be accomplished.
Chapter 1 17

18. Systems Development Life Cycle
(SDLC) (Cont.)
n Implementation – the information system
is coded, tested, installed and supported in
the organization.
n Maintenance – an information system is
systematically repaired and improved.
Chapter 1 18

19. Chapter 1 19

20. The Heart of the Systems Development
Process
Current practice combines analysis, design, and implementation
into a single iterative and parallel process of activities
Chapter 1 20

21. Traditional Waterfall SDLC
One phase begins
when another
completes, little
backtracking and
looping
Chapter 1 21

22. Problems with Waterfall Approach
n System requirements “locked in” after
being determined (can't change).
n Limited user involvement (only in
requirements phase).
n Too much focus on milestone deadlines of
SDLC phases to the detriment of sound
development practices.
Chapter 1 22

23. Different Approaches to Improving
Development
n Prototyping
n Computer­Aided Software
Engineering (CASE) Tools
n Joint Application Design (JAD)
Chapter 1 23

24. Different Approaches to Improving
Development (Cont.)
n Rapid Application Development
(RAD)
n Agile Methodologies
n eXtreme Programming
Chapter 1 24

25. Prototyping
n Iterative development process:
n Requirements quickly converted to a
working system.
n System is continually revised.
n Close collaboration between users and
analysts.
Chapter 1 25

26. Prototyping (Cont.)
Chapter 1 26

27. Computer­Aided Software
Engineering (CASE) Tools
n Diagramming tools enable graphical
representation.
n Computer displays and report generators
help prototype how systems “look and
feel”.
Chapter 1 27

28. Computer­Aided Software
Engineering (CASE) Tools (Cont.)
n Analysis tools automatically check for
consistency in diagrams, forms, and
reports.
n Central repository for integrated storage of
diagrams, reports, and project
management specifications.
Chapter 1 28

29. Computer­Aided Software
Engineering (CASE) Tools (Cont.)
n Documentation generators standardize
technical and user documentation.
n Code generators enable automatic
generation of programs and database
code directly from design documents,
diagrams, forms, and reports.
Chapter 1 29

30. CASE Tools (Cont.)
Figure 1­12 A class diagram from IBM’s Rational Rose
Chapter 1 30

31. CASE Tools (Cont.)
Chapter 1 31

32. Joint Application Design (JAD)
n Structured process involving users,
analysts, and managers.
n Several­day intensive workgroup sessions.
n Purpose: to specify or review system
requirements.
Chapter 1 32

33. Rapid Application Development
(RAD)
n Methodology to radically decrease
design and implementation time.
n Involves: extensive user involvement,
prototyping, JAD sessions, integrated
CASE tools, and code generators.
Chapter 1 33

34. Rapid Application Development
(RAD) (Cont.)
Chapter 1 34

35. Agile Methodologies
n Motivated by recognition of software
development as fluid, unpredictable, and
dynamic.
n Three key principles
¨ Adaptive rather than predictive.
¨ Emphasize people rather than roles.
¨ Self­adaptive processes.
Chapter 1 35

36. Agile Methodologies (Cont.)
Chapter 1 36

37. eXtreme Programming
n Short, incremental development cycles.
n Automated tests.
n Two­person programming teams.
Chapter 1 37

38. eXtreme Programming (Cont.)
n Coding and testing operate together.
n Advantages:
¨ Communication between developers.
¨ High level of productivity.
¨ High­quality code.
Chapter 1 38

39. Object­Oriented Analysis and
Design (OOAD)
n Based on objects rather than data or
processes.
n Object: a structure encapsulating
attributes and behaviors of a real­
world entity.
Chapter 1 39

40. Object­Oriented Analysis and
Design (OOAD) (Cont.)
n Object class: a logical grouping of
objects sharing the same attributes
and behaviors.
n Inheritance: hierarchical
arrangement of classes enable
subclasses to inherit properties of
superclasses.
Chapter 1 40

41. Rational Unified Process (RUP)
n An object­oriented systems development
methodology.
n RUP establishes four phase of
development: inception, elaboration,
construction, and transition.
n Each phase is organized into a number of
separate iterations.
Chapter 1 41

42. Phases of OOSAD­based
Development
Figure 1­14 Phases of OOSAD­based development
Chapter 1 42

43. Our Approach to Systems
Development
n The SDLC is an organizing and guiding
principle in this book.
n We may construct artificial boundaries or
artificially separate activities and
processes for learning purposes.
n Our intent is to help you understand all the
pieces and how to assemble them.
Chapter 1 43

44. Summary
n In this chapter you learned how to:
ü Define information systems analysis and
design.
ü Describe the different types of information
systems.
ü Describe the information Systems
Development Life Cycle (SDLC).
Chapter 1 44

45. Summary (Cont.)
ü Explain Rapid Application Development
(RAD), prototyping, Joint Application
Development (JAD), and Computer Aided
Software Engineering (CASE).
ü Describe agile methodologies and eXtreme
programming.
ü Explain Object Oriented Analysis and
Design and the Rational Unified Process
(RUP).
Chapter 1 45