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Introduction to Systems Analysis and

Design

Shelly Cashman Rosenblatt

Systems Analysis and Design 4e

Chapter 1

Introduction to Systems Analysis

and Design


Objectives

Discuss the impact of information

technology on business operations

Describe an information system and

explain its components and

characteristics

Identify common types of information

systems and explain who uses them

Distinguish between structured

analysis and object-oriented

methodology


Objectives

Explain systems development

techniques and tools, including

modeling, prototyping, and CASE tools

Describe the systems development life

cycle

Discuss the role of the information

technology department and the

systems analysts who work there


Why do businesses depend on

information more than ever?

Global competition

Intense pressure for quality

Information technology can mean

the difference between survival and

failure

Introduction

•Successful firms treat information as a vital asset that

must be used effectively, updated constantly, and

safeguarded carefully.

Introduction

What is Information Technology?

IT is driving a new economy

Most businesses give IT budget a

relatively high priority

Information System Development

is a step-by-step process

An information system combines

IT, people and data to support

business requirements Systems Analysis and Design 4e


What is required for successful

business information systems?

The right hardware and software

System analyst plan develop, and

maintain information systems.

A team of talented, motivated

people who use information

technology to achieve business

goals

Introduction


Who develops information

systems?

Traditionally, a company either

develops its own information

system, called in-house app.

Or purchases a system called

software package

Today the choice is much more

complex

The greatest risk: how before what

Introduction


Introduction

IBM summed it up this way:

“Information system professionals

need to work closely with managers

and users to create a shared

business model…”


IT professionals must understand

a company’s business operations

to design successful system.

Each business situation is different

e.g. hotel chain

Each business has its own unique

requirements

Understanding the business


Business Process Modeling

Business process modeling is

used to represent a company’s

operations and information needs

Business process modeling

requires a business profile and a

series of models that documents

various business processes.


Systems and Procedures

Business process modeling is

used to represent a company’s

operations and information needs

Business profiles, models, and

processes

Business profile

Business model

Business process reengineering


Systems and Procedures


Information System Components

A system is a set of related

components that produces specific

result.

Hardware

Software

Data

Processes

People




Hardware is the physical layer of

the information system



Software

System software controls the

hardware and software environment

and includes the operating system

Application software consists of

programs that that process data to

produce information Horizontal system such as inventory, payroll

Vertical system such as medical practice

A company must consider interaction of new

system with legacy systems



Computer Software

Application Software System Software

General Purpose

Application

Programs

Application

Specific

Programs

System

development

programs

System

management

programs

•Software suites

•Web browsers

•Electronic mail

•Word processing

•Spreadsheets

•Database managers

•Presentation graphics

•Personal information

managers

•groupware

•Business-accounting

Transaction processing

CRM

ERP

EC

•Science and Engineering

•Education,

Entertainment

•Operating systems

•Network management

programs

•Database management

systems

•Application servers

•System utilities

•Performance and security

monitors

•Programming

language translators

•Programming editors

and tools

•CASE packages


Data stored in files and databases

is a vital component of every

system



Processes define the tasks and

business functions that must be

performed by users, managers,

and IS staff to achieve specific

result.



People who use the system are

called users, or end users, and

include employees, customers,

vendors, or others who interact

with the system



Business Information Systems

Companies are classified based

on their main activities:

Production-oriented (industrial )

companies that manufacture & sell

goods

Service companies that mainly offer

information, services, or sell goods

made by others

Internet-dependent firms – dot-com

(.com)



Internet-based commerce is

called e-commerce or I-commerce

The growth of e-commerce

B2C (Business-to-Consumer)

B2B (Business-to-Business)

New roles and opportunities for

systems analysts


Web-Based System Development

Internet-based development is

changing rapidly

Software industry compete in

market for overall software

services, rather individual

products

These services include Powerful development environment

Software solution e.g. WebShpere or .Net

Many firms offer Web Services



Characteristics of business

information systems

4 main characteristics affect a

business information system’s

complexity

Relationships with other systems

Boundaries

Specialized business needs

Size of the company


Types of Information Systems

Traditional categories

Operational systems

Management information systems

Decision support systems

Executive information systems

Expert systems

Office systems



Enterprise computing systems

Support company-wide data

management requirements

Enterprise resource planning (ERP)

The main objective of enterprise computing is to

integrate a company’s primary functions (such as

production, sales, services, inventory control,

and accounting) to improve efficiency, reduce costs, and

help managers make key decisions.



Transaction processing systems

TP systems data generated by day-

to-day business operations

TP and online transaction processing

(OLTP)

TP captures data and triggers

updates

TP ensures data integrity





Business support systems

Provide job-related information to

users at all levels in the company

Management information systems

(MIS)

What-if analysis

Decision support



Knowledge management systems

Expert systems

Simulate human reasoning by

combining data with inference rules

Fuzzy logic


User productivity systems

Tools to improve quality and job

performance

Word processing is an example

Information systems integration

Important that all information systems

can communicate intelligently



Four organizational levels

Operational employees

Empowerment

Lower management

Operational plans

Middle management

Tactical planning

Top management

Strategic planning

Organizational Structure


Organizational Structure


Systems Development Techniques and Tools



Modeling

Graphical representation of a concept or process

Business model

Requirements model

Data model

Object model

Network model

Process model


Prototyping

Early working version of the system

Allows analysis before final

decisions are made




Computer-aided systems

engineering (CASE)

Framework for systems design and

analysis

Upper CASE tools

Lower CASE tools



Joint application development

and rapid application development

JAD – Team based fact finding

techniques

RAD – Condense development

process



Other systems development tools

Word processing

Spreadsheets

Presentation software


Overview of Systems Development Methodologies

Structured Analysis

Process-centered

Uses systems development life

cycle (SDLC)

Developing into a technique known

as information engineering


Systems planning

Systems analysis

Systems design

Systems implementation

Systems operation and support

Waterfall model

Systems Development Life Cycle




Systems planning

Systems analysis

Systems design

Systems implementation

Systems operation and support

Waterfall model

Interactive model





Systems planning

Purpose – identify problem’s nature/scope

Systems request – begins the process & describes desired changes/improvements

Systems planning – includes preliminary investigation or feasibility study

End product – preliminary investigation report



Systems analysis

Purpose is to learn exactly how the

current system operates

Fact-finding or requirements

determination is used to define all

functions of the current system



Options Develop a system in-house

Purchase a commercial package

Modify an existing system

Stop development

The end product for this phase is the

systems requirements document



Systems design

Purpose is to satisfy all documented

requirements

Identify all outputs, inputs, files,

manual procedures, & application

programs

Avoid misunderstanding through

manager and user involvement

End product is system design

specification



Systems implementationConstruct/deliver information system Prepares functioning, documented

systemWrite, test, document application

programsUser and manager approval obtainedFile conversion occursUsers, managers, IS staff trained to

operate and support the systemPost-implementation evaluation

performed



Systems operation and supportNew system supports business

operations

Maintenance changes correct errors or meet requirements

Enhancements increase system capability

After several years of operation, systems experience need for extensive changes

Systems development life cycle ends with system replacement




Systems development guidelines

Stick to a plan

Involve users

Identify milestones

Establish checkpoints

Be flexible

Provide accurate and reliable cost and

benefit information


Information Technology Department

Operations group responsible for

centralized computers and

processing

Technical support group installs and

supports systems software and

serves in an advisory and support

capacity to other groups in the IS

department





Application development

Systems support

User support

Database administration

Network administration

Web support


The Systems Analyst Position

Responsibilities

Required skills and background

Certification issues

Career opportunities


Background and history

Company organization chart

IT department structure

SOFTWEAR, LIMITED


SOFTWEAR, LIMITED

Background and history Manufactures and sells casual and

recreational clothing

Formed in 1991

$250 million total 1997 sales

Total of 450 employees

California & Texas manufacturing

plants

125 people work at SWL’s

headquarters in Raleigh, N.C.

SWL maintains a Web site


Company organization chart

President, Robert Lansing – four direct reports

Vice President Operations, David Josephs

Vice President Marketing, Amy Neal

Vice President Finance, Michael Jeremy

Vice President Human Resources, Tina Pham

SOFTWEAR, LIMITED


SOFTWEAR, LIMITED


Company organization chart President, Robert Lansing – four

direct reports Vice President Operations, David

Josephs Vice President Marketing, Amy

Neal Vice President Finance, Michael

Jeremy Director of Information Technology,

Ann Hon, reports to the Vice President Finance, Michael Jeremy

Vice President Human Resources, Tina Pham

SOFTWEAR, LIMITED


SOFTWEAR, LIMITED


SOFTWEAR, LIMITED

IT department structure

Director of Information Technology,

Ann Hon, has three direct reports

Manager Systems Support, Jane

Rossman

Manager User Support, Kerry

Krauss

Manager Web Support, Altovise

Martin


SOFTWEAR, LIMITED

End

Chapter 1

Documents

Introduction to Systems Analysis and Design - Wikispacesmaqsodi.wikispaces.com/file/view/SAD.pdf · Introduction to Systems Analysis and ... Avoid misunderstanding through manager