Chapter 1
Introduction to Systems Analysis
and Design
BISI 4230
Summer ‘05
Chapter Objectives
• Discuss the impact of information
technology on business
• Describe an information system and
explain its components
• Use profiles and models to understand
business functions and operations
• Understand the impact of the Internet on
business
• Identify various types of information
systems and explain who uses them
Chapter Objectives
• Explain systems development tools,
including modeling, prototyping, and
CASE tools
• Distinguish between structured analysis
and object-oriented methodology
• Describe the systems development life
cycle
• Discuss the role of the information
technology department and the systems
analysts who work there
Introduction
• Information technology can mean the
difference between success and failure
• Companies use information as a weapon to:
– increase productivity,
– deliver quality products and services,
– maintain customer loyalty, and
– make sound decisions.
Figure 1-1
The Impact of Information
Technology
• Information Technology
– Combination of hardware and software
products and services that companies use to
manage, access, communicate, and share
information
– A vital asset that must be used effectively,
updated constantly, and safeguarded carefully
The Impact of Information
Technology
• The Future of IT
– Responsible for half of all productivity growth
and a third of all economic growth between
1995-1999
– Online population worldwide is expected to
increase 60 percent between 2001-2004
The Impact of Information
Technology
• The Role of Systems Analysis and Design
– Systems Analysis and Design
• Step-by-step process for developing high-quality
information systems
– Systems Analyst
• Plan, develop, and maintain information systems
The Systems Analyst Position
• A systems analyst investigates, analyzes,
designs, develops, installs, evaluates, and
maintains a company’s information
systems
• On large projects, the analyst works as a
member of an IT department team
• Smaller companies often use consultants
to perform the work
The Systems Analyst Position
• Responsibilities
– Translate business requirements into practical
IT projects to meet needs
• Required Skills and Background
– Solid communication skills and analytic ability
Figure 1-31
The Impact of Information
Technology
• Who develops Information Systems?
– In-house applications
– Software packages
– Internet-based application services
– Outsourcing
– Custom solutions
– Enterprise-wide software strategies
• Risk in launching new IS
– How versus What
Information System
Components
• A system is a set of related components
that produces specific results
• A Mission-critical system is one that is vital
to a company’s operations
• Information systems have five key
components: hardware, software, data,
processes, and people
Figure 1-9
Information System
Components
• Hardware
– Is the physical layer of the information system
– Moore’s Law
• Processing power doubles every 18 months
Information System
Components
• Software
– Programs (set of instructions) that control hardware
– System software
•
•
•
•
[Network] operating system
Utility programs
Device drivers
Security software
– Application software
• Enterprise applications
• Horizontal system
• Vertical system
Information System
Components
• Data
– Is the raw material that an information system
transforms into useful information
Figure 1-11
Information System
Components
• Processes
– Define the tasks and business functions that
users, managers, and IT staff members
perform to achieve specific results
• People
– Users, or end users, are the people who
interact with an information system, both
inside and outside the company
Understanding The Business
What are the business operations?
• Business Process Modeling
• Business Profile
– Business models
• Business process(es)
– BPR (business process reengineering)
Figure 1-12
Understanding The Business
New Kinds of Companies
– Companies are classified based on their main
activities:
• Traditional companies
– Production-oriented
– Service-oriented
Figure 1-14
• Internet-dependent
– Brick-and-mortar vs.
pure-play/click-through/Dot-com(.com)
Impact of the Internet
• E-Commerce (I-Commerce)
– B2C (Business-to-Consumer)
– B2B (Business-to-Business)
• EDI
• Web-Based System Development
– WebSphere
– .NET
– J2EE
How Business Uses Information
Systems
• In past, IT managers divided systems into
categories based on the user group the
system served
– Office systems (admin staff)
– Operational systems (operational personnel)
– Decision support systems (middle m’gers)
– Executive information systems (top m’gers)
How Business Uses Information
Systems
• Today, it makes more sense to identify a
system by its functions & features, rather
than by users
– Enterprise computing systems
– Transaction processing systems
– Business support systems
– Knowledge management systems
– User productivity systems
Information System Users and
Their Needs
• A systems analyst must understand the
company’s organizational model in order
to recognize who is responsible for
specific processes and decisions and to
be aware of what information is required
by whom.
Figure 1-21
Systems Development Tools
and Techniques
• Systems analysts must know how to use a
variety of techniques such as
– [business operations],
– modeling,
– prototyping, and
– computer-aided systems engineering
tools to plan, design, and implement IS
• Systems analysts work with these tools in
a team environment
Systems Development Tools
and Techniques
• Modeling
– Model = a graphical of a concept or process
•
•
•
•
•
Business/Requirements model
Data model
Object model
Network model
Process model
Systems Development Tools
and Techniques
• Prototyping
– Early working version of an information
system [tests system concepts]
– Speeds up the development process
significantly
– Important decisions might be made too early,
before business or IT issues are thoroughly
understood
Systems Development Tools
and Techniques
• Computer-Aided Systems/Software
Engineering (CASE) Tools
– Framework for systems development and
support a wide variety of design
methodologies
– CASE tools
Figure 1-24
Systems Development Methods
• Structured analysis and object-oriented
analysis are both popular methodologies
for developing computer-based
information systems.
• A systems analyst should understand the
alternative methodologies and their
individual strengths and weaknesses.
Systems Development Methods
• Structured Analysis
– Uses a set of process models to describe a
system graphically
Figure 1-25
– Systems development life cycle (SDLC)
• Series of phases in structures analysis
• Plan, Analyze, Design, Implement, Support
Systems Development Methods
• Object-oriented (O-O) analysis
– O-O analysis combines data & processes into
objects
– Objects possess properties and methods
– Methods change an object’s properties
– Messages request specific behavior or
information from another object
Figure 1-26
Systems Development Methods
• Joint Application Development and Rapid
Application Development
– JAD – Team based fact finding
– RAD – compressed version of the entire
process
The Systems Development Life
Cycle
• It includes the following steps:
– Systems planning
– Systems analysis
– Systems design
– Systems implementation
– Systems operation and support
The Systems Development Life
Cycle
• Traditionally pictured as a waterfall model,
but is also presented as an interactive
model depicting real world practice and
the constant dialog among users,
managers, and systems developers
Figure 1-28
Figure 1-29
The Systems Development Life
Cycle
• Systems planning
– Purpose is to identify the nature and scope of
the business opportunity or problem
– Systems request – begins the process &
describes problems or desired changes
– Systems planning includes preliminary
investigation whose key part is a feasibility
study
The Systems Development Life
Cycle
• Systems Analysis
– Purpose is to build a logical model of the new
system
– First step is requirements modeling, where
you investigate business processes and
document what the new system must do
– End product is the System requirements
document
The Systems Development Life
Cycle
• Systems Design
– Purpose is to create a blueprint that will
satisfy all documented requirements
– Identify all outputs, inputs, and processes
– Avoid misunderstanding through manager
and user involvement
– End product is system design specification
The Systems Development Life
Cycle
• Systems Implementation
– New system is constructed
– Write, test, & document programs
– File conversion occurs
– Users, managers, IT staff trained to operate
and support the system
– System evaluation performed
The Systems Development Life
Cycle
• Systems Operation and Support
– New system supports operations
– Maintenance changes correct errors or meet
requirements
– Enhancements increase system capability
– After several years of operation, systems
need extensive changes
– SDLC ends with system replacement
Information Technology
Department
• The information technology (IT)
department develops and maintains a
company’s information systems.
• The IT group provides technical support
– includes six main functions: application
development, systems support, user support,
database administration, network
administration, and Web support
Figure 1-30
Information Technology
Department
• Application Development
– Team may include users, managers and IT
Staff members
• Systems Support
– Provides hardware and software support
• User Support
– Provides users with technical information,
training, and productivity support
Information Technology
Department
• Database Administration
– Database design, management, security,
backup, and user access
• Network Administration
– Includes hardware and software maintenance,
support, and security
• Web Support
– Design and construction of web pages and
presence. Important for e-commerce
The Systems Analyst Position
• Certification
– Professional credential
• Career Opportunities
– Job titles
– Company organization
– Company size
– Corporate culture
– Salary, location, and future growth
Test Yourself
1. In order to best support user’s IT needs,
IT professionals need to understand the
company’s business operations. What
process might a system analyst use to
accomplish this?
Test Yourself
1. In order to best support user’s IT needs,
IT professionals need to understand the
company’s business operations. What
process might a system analyst use to
accomplish this?
– Business process modeling is used to
represent a company’s operations and
information needs
Test Yourself
2. What are the five key components of
information systems?
Test Yourself
2. What are the five key components of
information systems?
Hardware
Software
Data
Processes
People
Test Yourself
3. How are business information systems
identified?
Test Yourself
3. How are business information systems
identified?
– Functions and features
Test Yourself
4. T/F: An enterprise computing system is
highly specialized and targeted for a
company’s top executives.
Test Yourself
4. T/F: An enterprise computing system is
highly specialized and targeted for a
company’s top executives.
False. Enterprise computing systems support
company-wide data management
requirements
Test Yourself
5. Top management is typically
responsible for ________ planning,
while middle management focuses on
__________ planning.
Test Yourself
5. Top management is typically
responsible for strategic planning,
while middle management focuses on
tactical planning.
Test Yourself
6. CASE tools are:
a) an object oriented methodology
b) techniques or tools to help plan and
design information systems
c) team-based fact finding techniques
Test Yourself
6. CASE tools are:
a) an object oriented methodology
b) techniques or tools to help plan and
design information systems
c) team-based fact finding techniques
Test Yourself
7. Objects, classes, and methods are all
terms used in structured/object oriented
methodologies
Test Yourself
7. Objects, classes, and methods are all
terms used in structured/ object oriented
methodologies
Test Yourself
8. What are the phases of the systems
development life cycle?
Test Yourself
8. What are the phases of the systems
development life cycle?
–
–
–
–
–
Systems planning
Systems analysis
Systems design
Systems implementation
Systems operation and support
Test Yourself
9. List at least three of the six functions of a
typical IT department
Test Yourself
9. List at least three of the six functions of a
typical IT department
1.
2.
3.
4.
5.
6.
Application development
Systems support
User support
Database administration
Network administration
Web support
Test Yourself
10. T/F Certification is a professional
credential that is valued by little (if any)
companies.
Test Yourself
10. T/F Certification is a professional
credential that is valued by little (if any)
companies.
False
End Chapter 1