Systems Analysis & Design
Seventh Edition
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CHAP1: INTRO TO SAD
CHAPTER OBJECTIVES
Discuss the impact of information technology on
business strategy and success
Define and describe an information system
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
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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
The use of information
as a weapon in the battle
increase productivity,
deliver quality products and services,
maintain customer loyalty
make correct/strong decisions
IT can mean the difference between success and
failure
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THE IMPACT OF INFORMATION
TECHNOLOGY
Definition: Information Technology (IT)
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
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
305.5% usage growth 2000-2008
Note: http://www.internetworldstats.com/
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THE IMPACT OF INFORMATION
TECHNOLOGY
The Role of Systems Analysis and Design
Definition: Systems Analysis and Design
Step-by-step process for developing high-quality
information systems
Systems Analyst (SA)
Plan, develop, and maintain information systems
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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
How versus What – how the system will be
implemented before determining what the system is
supposed to do = high risk
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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
Business cannot be done
without it
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INFORMATION SYSTEM COMPONENTS
1) Hardware – consist of everything in the physical
layer of the information system
Servers, workstations, networks, telecommunications
equipment, etc
2) Software – program that control the h/ware and
produce the desired result
System software – manage h/ware component (e.g. Win
XP)
Network operating system – (e.g. Win 2003 Server,
Unix, etc)
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INFORMATION SYSTEM COMPONENTS
Application software – consist of program that support
day-to-day business functions
Enterprise applications – order process system, payroll
system, financial system
Horizontal system – inventory or payroll application
(e.g. standard payroll system that able to use by all
companies)
Vertical system – design to meet unique req. of a
business (e.g. special IS that serves to meet unique
business req.)
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INFORMATION SYSTEM COMPONENTS
3) Data
Is the raw material that an information system
transforms into useful information
Tables
Linking
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INFORMATION SYSTEM COMPONENTS
4) Processes
Define the tasks and business functions that users,
managers, and IT staff members perform to achieve
specific results
5) People (Stakeholder)
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 – describe company overall
function
Organization, processes, services,
products, customers, suppliers,
competitors, constraints, future direction
SA investigates company’s products,
services, Internet opportunities
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UNDERSTANDING THE BUSINESS
Business Models – purpose: make it easier for
manager and system analyst to understand day-today business operation
Business models – a framework in creating
value (e.g. selling computer – Dell)
Business process – specific (tasks|processes)
that involved in creating value
BPR (business process reengineering) –
trying to simplify current processes or reduce
cost
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UNDERSTANDING THE BUSINESS
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UNDERSTANDING THE BUSINESS
New Kinds of Companies
Product-oriented – routers,
microchips
Service-oriented – resellers and
providers of information
Brick-and-mortar – conduct business
from physical locations (have
premises)
Dot-com (.com) or Internetdependent
Amazon.com, Google, eBay, Yahoo!
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IMPACT OF THE INTERNET
E-Commerce (I-Commerce)
B2C (Business-to-Consumer)
B2B (Business-to-Business)
Electronic Data Interchange (EDI), XML, HTML
Web-Based Development Solutions
IBM WebSphere Modeler, Microsoft .NET
Web services
Developed by 3rd party developer but included as part of the
IS
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HOW BUSINESS USES INFORMATION
SYSTEMS
IT managers divided systems into categories
based on the user group the system served
Office systems
Operational systems
Decision support systems
Executive information systems
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HOW BUSINESS USES INFORMATION
SYSTEMS (TYPE OF IS)
Today, it makes more sense to identify a system by
its functions, rather than by users
Enterprise computing systems – support
company-wide operation and data mgt req.
Transaction processing systems – data generated
by day-to-day operations
Business support systems – provide job-related
information to users at all levels of a company
Knowledge management systems – expert
system, combine knowledge base and inference
rule
User productivity systems – email, voice mail,
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fax, etc
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HOW BUSINESS USES INFORMATION
SYSTEMS (TYPE OF IS)
Enterprise computing systems
Support company-wide operations and data
management requirements
Enterprise resource planning (ERP)
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HOW BUSINESS USES INFORMATION
SYSTEMS (TYPE OF IS)
Transaction processing systems (TPS)
Efficient because they process a set of transactionrelated commands as a group rather than individually
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HOW BUSINESS USES INFORMATION SYSTEMS
(TYPE OF IS)
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 analysis
e.g: What will happen if fuel price continues decreasing?
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HOW BUSINESS USES INFORMATION SYSTEMS
(TYPE OF IS)
Knowledge management systems
Called expert systems
Simulate human reasoning by combining a
knowledge base and inference rules
Many use fuzzy logic and neural network
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HOW BUSINESS USES INFORMATION SYSTEMS
(TYPE OF IS)
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
Common Object Request Broker Architecture (CORBA)
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INFORMATION SYSTEM USERS AND
THEIR NEEDS
A SA 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 – develop long range plans called
strategic plans, define the company overall
mission and goals (SISP)
Middle Managers and Knowledge Workers
- just below the top level, provide direction,
resources and performance feedback to teams
and supervisors
Supervisors and Team Leaders – carry out dayto-day functions and oversee operational
employees
Operational Employees – users who rely on TPS
to enter and receive data
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SYSTEMS DEVELOPMENT TOOLS AND
TECHNIQUES
SA 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
SA work with these tools in a team environment
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SYSTEMS DEVELOPMENT TOOLS AND
TECHNIQUES
Modeling
Used to describe and simplify an IS:
Business or requirements model – information
that a system must provide
Data model – data structures and design
Object model – consist of data and process
Network model – design and protocols of
telecomm. links
Process model – logic that programmers use to
write code modules
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SYSTEMS DEVELOPMENT TOOLS AND
TECHNIQUES
Prototyping
Definition: an early working version of an IS
Adv: Speeds up the development process
Disadv: 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 – make easier to built an information
system, boost IT productivity and improve the quality
of the finished product.
Upper CASE – (conceptual|logical) design
Lower CASE – physical design
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SYSTEMS DEVELOPMENT METHODS
Structured analysis and object-oriented analysis
are both popular methodologies for developing
computer-based information systems
A SA 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)
Spiral Model
Extreme Programming
RUP
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THE SYSTEMS DEVELOPMENT LIFE
CYCLE
SDLC used to plan and manage the systems
development process
It includes the following steps:
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
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
End product: Preliminary Investigation Document,
Software Development Plan (SDP)
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THE SYSTEMS DEVELOPMENT LIFE
CYCLE
Systems Analysis
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: 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: systems design specification
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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
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
Systems Support and Security
Team may include users, managers and IT staff
members
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
Network Administration
Database design, management, security, backup, and
user access
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
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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
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, serviceoriented, or a combination of the two
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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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