Introduction to System Analysis
and Design
Mirza Rehenuma Tabassum
Mark Distribution
Remarks
Distribution
Final Exam
50%
Mid Term
20%
Class Test (Four)
10%
Project Paper/Term Paper (Individual)/ Assignment
including Presentation
10%
Reference Book
System Analysis and Design
- Kendall & Kendall
System Analysis and Design
- Shelly & Rosenblatt
Avicenna
System Analysis and Design
Introduction
Organizations are large systems composed of
interrelated subsystems, IT affects productivity,
quality, customer loyalty, and help makes better
decisions.
To discover information requirements properly
System Analysis and Design
Introduction to SAD 5
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
Information is a vital asset that must be used
The Impact of Information
Technology
The Future of IT
IT has created a new economy, where
advances in hardware, software, networks
provide huge benefits to businesses
worldwide.
Globalization and the increasing internet users
around the world, give IT budgets high
System Analysis and Design
Introduction to SAD 7
Systems Analysis and Design
is the process people use to
create information systems
people
processes
data
software
hardware
The Impact of Information
Technology
What is Systems Analysis and Design (SAD)?
Systems Analysis:
understanding and specifying in detail whatan information system should do
System Design:
specifying in detail how the parts of aninformation system should be implemented
Why is it important?
Success of information systems depends on good SAD
Widely used in industry - proven techniques
System Analysis and Design
Introduction to SAD 9
The Impact of Information Technology
The Role of Systems Analysis and Design
Information Systems Analysis and Design
Step-by-step process by which computer-based
information systems are developed and maintained
Systems Analyst
is a key person analyzing business, depending on
organization function, requirements, identifying
opportunities for improvement, solving problems, and
designing information systems to implement these ideas.
Many failed systems were abandoned because analysts
The Impact of Information
Technology
Who develops Information Systems?
Before taking the decision to build
In-house applications
or
purchased systems from outside vendors
or both, the
organization must determine what the system is supposed
to do.
A company must begin to outlining its business needs and
possible IT solutions, then it can consider the
implementation options.
The choice is not easy because there are many options
include
Introduction to systems
Analysis, design, and development systems,
products, or services requires answering several
fundamental questions:
WHAT is a system?
What is an IS?
Characteristics of Systems.
Avicenna
System Analysis and Design
What is System
Interrelated components working together for a
common purpose
A system, by definition, is composed of
hierarchical levels of physical elements, entities,
or components.
A collection of components that work together to
What is System
Basically there are three major components in every
system, namely input, processing and output.
For example:
Human body represents a complete natural system.
We are also bound by many national systems such as political
system, economic system, educational system and so forth.
The objective of the system demand that some output is
produced as a result of processing the suitable inputs
What is an Information System?
Arrangement of people, data, processes,
information presentation and information
technology that interact to support and
Characteristics of Systems
Systems are made up of interrelated subsystems (e.g. a
nuclear reactor is composed of boilers, reactor components
etc.)
Functional decomposition – dividing a system into
components based on subsystems (which are in turn further
divided into subsystems)
System boundary – the separation between a system and
its environment (where inputs and outputs cross)
Automation boundary – separation between the automated
part of system and the manual part
Environment surrounding the system
Manual part
Characteristics of Systems
The system boundary and the automation
boundary
AutoAutomated part of the system
System
Boundary
Characteristics of Systems
General Depiction of a System
System Analysis and Design
Information System Components
Information systems have five key
Information System Components
Hardware
-Is the physical layer of the information system
Hardware includes: work stations, servers,
networks, telecommunication equipment,
cables, input and output devices and many
others.
Hardware has become more powerful that give
information systems more opportunities, and
it also cut costs by becoming less expensive
Avicenna
System Analysis and Design
Information System Components
Software
-Software refers to the programs which control the hardware and produce the desired information and results
Software consists of system software and application software
System software manages the hardware components, which can include a single workstation or global network. Examples of system software include
Operating systems
Security software, that protects the computer from intrusion
Utility programs, that handle specific tasks such as data backup and disk management.
Information System Components
Application software, the programs that support
day-to day business functions and provide process and manage the information user need. Application software can serve one or any number of users. Examples of
company-wide applications, called Enterprise
applications, include order processing system, payroll systems, and company communication network
Application software includes horizontal and vertical
systems
A horizontal system is a system, such as an inventory or
payroll application, that can be adapted for use in many different types of companies
A vertical systems is designed to meet the unique
requirements of a specific business, such as a medical practice, or a video chain.
Information System Components
Data
Is the raw material that an information system
transforms into useful information
Data can be stored in various locations, called tables
The system can extract specific information by linking
the tables
Processes
Define the tasks and business functions that users,
managers, and IT staff members perform to achieve
specific results
Processes are the building blocks of an information
Information System Components
People
Those who operate the system; those who provide its
inputs and consume its outputs, and those who provide manual processing activities in a system,
Users are the people who interact with an information system, both inside and outside the company
We can divide users to two types internal and
external
Internal users include administrators, managers, technicians,
sales staff, and corporate officers
External users include customers who track their orders on
the company’s Web site and suppliers who use a customer’s system to plan their manufacturing schedules.
System Analysis and Design
Reference
[1] System Analysis and Design, Sixth Edition
Authors: Gary B. Shelly, Thomas J. Cashman and Harry J. Rosenblatt , Publisher: SHELLY CASHMAN SEWIES.
[2] Modern Systems Analysis and Design Third Edition
