Chapter 01 – Intro to SAD

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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

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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
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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
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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
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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
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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
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
Network Administration

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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
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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, 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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