Systems Analysis & Design
Sixth Edition
Chapter 1
Chapter Objectives
● Discuss the impact of information
technology on business strategy and
success
● Define an information system and
describe its components
● Use profiles and models to understand
business functions and operations
● Explain how the Internet has affected
business strategies and relationships
● Identify various types of information
systems and explain who uses them
2
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
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Introduction
● Companies use
information as a weapon
in the battle to increase
productivity, deliver
quality products and
services, maintain
customer loyalty, and
make sound decisions
● Information technology
can mean the difference
between success and
failure
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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
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The Impact of Information
Technology
● The Future of IT
– Accounted for almost 30 percent of economic
growth in 2003
– Online population worldwide increased 106
percent between 2000-2004
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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
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The Impact of Information
Technology
● Who Develops Information Systems?
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In-house applications
Software packages
Internet-based application services
Outsourcing
Custom solutions
Enterprise-wide software strategies
How versus What
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Information System Components
● A system is a
set of related
components
that produces
specific results
● A missioncritical system
is one that is
vital to a
company’s
operations
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Information System Components
● Hardware
– Moore’s Law
● Software
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System software
Network operating system
Application software
Enterprise applications
Horizontal system
Vertical system
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Information System Components
● Data
– Is the raw material that an information system
transforms into useful information
– Tables
– Linking
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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
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Understanding The Business
● Business Profile
● Business Models
– Business models
– Business process
– BPR (business process reengineering)
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Understanding The Business
● New Kinds of Companies
– Companies are classified
based on their main
activities:
– Product-oriented
– Service-oriented
– Brick-and-mortar
– Dot-com (.com) or Internetdependent
14
Impact of the Internet
● E-Commerce (I-Commerce)
● B2C (Business-to-Consumer)
● B2B (Business-to-Business)
– EDI, XML, HTML
● Web-Based Development
– WebSphere, .NET
– Web services
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How Business Uses Information
Systems
● In past, IT managers divided systems
into categories based on the user group
the system served
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Office systems
Operational systems
Decision support systems
Executive information systems
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How Business Uses Information
Systems
● Today, it makes more sense to identify a
system by its functions, rather than by
users
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Enterprise computing systems
Transaction processing systems
Business support systems
Knowledge management systems
User productivity systems
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How Business Uses Information
Systems
● Enterprise computing systems
– Support company-wide operations and data
management requirements
– Enterprise resource planning (ERP)
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How Business Uses Information
Systems
● Transaction
processing systems
– Efficient because they
process a set of
transaction-related
commands as a group
rather than
individually
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How Business Uses Information
Systems
● Business support
systems
– Provide job-related
information to users
at all levels of a
company
– Management
information systems
(MIS)
– Radio frequency
identification (RFID)
– What-if
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How Business Uses Information
Systems
● Knowledge management systems
– Called expert systems
– Simulate human reasoning by combining a
knowledge base and inference rules
– Many use fuzzy logic
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How Business Uses Information
Systems
● User productivity systems
– Technology that improves productivity
– Groupware
● Information systems integration
– Most large companies require systems that
combine transaction processing, business
support, knowledge management, and user
productivity features
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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
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Information System Users and Their
Needs
● Top managers
● Middle Managers and Knowledge
Workers
● Supervisors and Team Leaders
● Operational Employees
● Strategic plans
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Systems Development Tools and
Techniques
● Systems analysts must know how to use
a variety of techniques such as
modeling, prototyping, and computeraided systems engineering tools to plan,
design, and implement information
systems
● Systems analysts work with these tools
in a team environment
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Systems Development Tools and
Techniques
● Modeling
– Used to describe and simplify an information
system:
– Business model
– Requirements model
– Data model
– Object model
– Network model
– Process model
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Systems Development Tools and
Techniques
● Prototyping
– Prototype
– Speeds up the development process
significantly
– Important decisions might be made too early,
before business or IT issues are thoroughly
understood
– Can be an extremely valuable tool
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Systems Development Tools and
Techniques
● Computer-Aided Systems Engineering
(CASE) Tools
– Framework for systems development and
support a wide variety of design methodologies
– CASE tools
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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
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Systems Development Methods
● Structured Analysis
– Uses a set of process models to describe a
system graphically
– Systems development life cycle (SDLC)
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Systems Development Methods
● Object-oriented (O-O) analysis
– O-O analysis combines data & processes into
objects
– Object is a member of a class
– Class is a collection of similar objects
– Objects possess properties
– Methods change an object’s properties
– Messages request specific behavior or
information from another object
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Systems Development Methods
● Joint Application Development and Rapid
Application Development
– JAD – Team based fact finding
– RAD – compressed version of the entire process
● Other development methodologies
– Microsoft Solutions Framework (MSF)
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The Systems Development Life Cycle
● SDLC used to plan and manage the
systems development process
● It includes the following steps:
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Systems planning phase
Systems analysis phase
Systems design phase
Systems implementation phase
Systems operation, support, and security phase
Deliverable or end product
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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
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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
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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
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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 systems design specification
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The Systems Development Life Cycle
● Systems Implementation
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New system is constructed
Write, test, & document programs
File conversion occurs
Users, managers, IT staff trained to operate and
support the system
– Systems evaluation performed
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The Systems Development Life Cycle
● Systems operation, support, and security
– New system supports operations
– Maintenance changes correct errors or meet
requirements
– Enhancements increase system capability
– Well-designed system will be secure, reliable,
maintainable, and scalable
– SDLC ends with system replacement
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Systems Development Guidelines
– Planning
– Involve users throughout the development
process
– Listening is very important
– Create a time table with major milestones
– Identify interim checkpoints
– Remain flexible
– Develop accurate cost and benefit information
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Information Technology Department
● The information technology (IT)
department develops and maintains a
company’s information systems
● The IT group provides technical support
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Information Technology Department
● Application Development
– Team may include users, managers and IT staff
members
● Systems Support and Security
– Provides hardware and software support
● User Support
– Provides users with technical information,
training, and productivity support
– Help desk
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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
– Webmaster
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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
44
The Systems Analyst Position
● Responsibilities
– Translate business requirements into practical IT
projects to meet needs
● Required Skills and Background
– Solid communication skills and analytical ability
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The Systems Analyst Position
● Certification
– Professional credential
● Career Opportunities
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Job titles
Company organization
Company size
Corporate culture
Salary, location, and future growth
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Chapter Summary
● IT is a combination of hardware and
software that support business
● The essential components of an
information system are hardware,
software, data, processes, and people
● Companies are product-oriented,
service-oriented, or a combination of the
two
47
Chapter Summary
● Organization structure usually includes
levels. Each level has different
responsibilities and information needs
● Systems analysts use modeling,
prototyping, and CASE tools. Modeling
produces a graphical representation of
the process, prototyping involves
creation of an early working model, and
CASE tools assist in various systems
development tasks
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Chapter Summary
● The Systems Development Life Cycle
(SDLC) consists of five phases: systems
planning, systems analysis, systems
design, systems implementation, and
systems operation, support, and security
● Systems analysts need a combination of
technical and business knowledge,
analytical ability, and communication
skills
● Chapter 1 Complete
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