System Development

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Information System

Development

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Learning Outcomes

Discuss the importance of project management, feasibility assessment, documentation, data and information

gathering techniques, and information systems security during

system development

Discuss the importance of project management, feasibility assessment, documentation, data and information

gathering techniques, and information systems security during

system development

Discuss the purpose of each phase in the system development cycle

Discuss the purpose of each phase in the system development cycle

Students should be able to…

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The System Development Life CycleWhat is an information system (IS)?

Hardware, software, data, people, and

procedures that work together to produce quality information

Hardware, software, data, people, and

procedures that work together to produce quality information

System—Set of components that

interact to achieve common goal

System—Set of components that

interact to achieve common goal

Businesses use many types of systems

Businesses use many types of systems

Hardw are

Softw are

Data

People

Procedures

1996 2007

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Phase 1. Planning

Phase 2. Analysis

Phase 3. Design

Phase 4. Implementation

Phase 5. Operating, Support, and Security

Review project requests Prioritize project

requests Allocate resources Form project

development team

Conduct preliminary investigation Perform detailed analysis activities:

Study current system

Determine user requirements

Recommend solution

Acquire hardware and software, if necessary

Develop details of system

Develop programs, if necessary Install and test new system Train users Convert to new system

Perform maintenance activities Monitor system performance Assess system security

The System Development Life CycleWhat are the phases of the system

development life cycle?

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Arrange tasks into phasesphases (groups of

activities)

The System Development Life CycleWhat are guidelines for system development?

Involve usersusers (anyone for whom system is being built)

Develop clearly defined standardsstandards (procedures company expects

employees to follow)

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The System Development Life CycleWho participates in the system development life cycle?

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The System Development Life CycleWhat is a systems analyst? A person!!!

Responsible for Responsible for designing and designing and

developing developing information information

systemssystemsthe “End Users”the “End Users”

(stakeholders)(stakeholders)

primary contact primary contact personperson

A person(s) playing the “role” of systems analyst is:

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The System Development Life CycleWhat is the project team?

Consists of users, systems analyst, and other IT professionals

Formed to work on a project from beginning to end

Project leader Project leader — one member of the team who manages and controls the project budget and

schedule

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The System Development Life CycleWhat is project management?

Process of planning, scheduling, and

controlling activities during system

development cycle

Project leader identifies elements for

projectRequired activities Required activities & roles played to & roles played to

fulfill the activitiesfulfill the activities

Required activities Required activities & roles played to & roles played to

fulfill the activitiesfulfill the activities

Goal, objectives, Goal, objectives, and expectations, and expectations, collectively called collectively called

scopescope

Goal, objectives, Goal, objectives, and expectations, and expectations, collectively called collectively called

scopescope

Time estimates for Time estimates for each activityeach activity

Time estimates for Time estimates for each activityeach activity

Cost estimates for Cost estimates for each activityeach activity

Cost estimates for Cost estimates for each activityeach activity

Activities that can Activities that can take place at same take place at same

timetime

Activities that can Activities that can take place at same take place at same

timetimeOrder of activitiesOrder of activitiesOrder of activitiesOrder of activities

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The System Development Life CycleWhat is a Gantt chart?

Popular tool used to plan and schedule

time relationships among project

activities

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The System Development Life CycleWhat is feasibility?

Measure of how

suitable system

development will be to

the company

Operational

feasibility

Schedule feasibilit

y

Four feasibility

tests:

Technical feasibilit

y

Economic feasibility

(also called

cost/benefit

feasibility)

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The System Development Life CycleWhat is documentation?

Includes reports, diagrams, Includes reports, diagrams, programs, and other programs, and other

deliverablesdeliverables

Collection and summarization Collection and summarization

of data and informationof data and information

Online Help too!!!

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The System Development Life CycleWhat are six data and information gathering techniques?

Review documentation Observe Questionnaire Interview Joint-application

design (JAD) session Research

JAD Session in Progress

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The System Development Life CycleWhat are some reasons to create or modify an information system?

Competition can lead to change

To improve existing system

Outside group may mandate change

To correct problem in existing system

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The System Development Life CycleWhat is the planning phase?

Begins when steering committee receives project request

Steering Steering committee committee — —

decision-making decision-making body for the body for the

companycompany

Function of committee:

Review and Review and approve approve project project

requestsrequests

Allocate Allocate resourcesresources

Form project Form project developmendevelopment team for t team for

each each approved approved projectproject

Prioritize Prioritize project project

requestsrequests

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The System Development Life CycleWhat is the analysis phase?

Conduct preliminary Conduct preliminary investigation, also investigation, also

called feasibility called feasibility studystudy

Perform Perform detailed detailed analysisanalysis

Operational

feasibility

Schedule feasibilit

y

Four feasibility

tests:

Technical

feasibility

Economic

feasibility

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The System Development Life CycleWhat are possible solutions?

Buy packaged software packaged software —prewritten software available

for purchase

Buy packaged software packaged software —prewritten software available

for purchase

Outsource Outsource — have outside source develop software

Outsource Outsource — have outside source develop software

Write own custom software custom software —software developed at user’s

request

Write own custom software custom software —software developed at user’s

request

Vertical market software—designed for

particular industry

Vertical market software—designed for

particular industry

Horizontal market

software—meets needs of many

companies

Horizontal market

software—meets needs of many

companies

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The System Development Life CycleWhat is the design phase?

Acquire hardware and softwareAcquire hardware and software

Develop all details of new or modified information

system

Develop all details of new or modified information

system

Includes several activities

Database design

Database design

Input and output design

Input and output design

Program design

Program design

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The System Development Life CycleWhat is a prototype? A working model of

the proposed systemA working model of the proposed system

Mockup is a sample of input and/or output:

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The System Development Life CycleWhat is computer-aided software engineering

(CASE)? Software tools designed to support

activities of the system development life cycle

Two popular Examples: • Microsoft’s Visual Studio• Eclipse

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Convert to new systemConvert to new system

The System Development Life CycleWhat is the implementation phase? Purpose is to construct, or build, new or

modified system and then deliver it to users

Train usersTrain users

Install and test new systemInstall and test new system

Develop programsDevelop programs

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The System Development Life Cycle

What are the four types of tests performed by system developers?

Verifies application works with

other applications

Systems test

Integration Test

Unit Test

Verifies each individual

program works by itself

Verifies all programs in the

application work together

Verifies the new system works

with actual data

Acceptance Test

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The System Development Life CycleWhat are conversion strategies? Used to switch from old system to new

system

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The System Development Life CycleWhat is the operation, support, and security phase?

Perform maintenance activities

Monitor system performance

Assess system security

Provides ongoing assistance after system is implemented

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The System Development Life Cycle

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Programming Languages

What is a computer program (software)? Set of instructions that directs

the computer to perform tasks Programming language—used to

communicate instructions

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Programming Languages…”in the beginning”

What is machine language? Only language

computer directly recognizes

Uses a series of binary digits (1s and 0s) with a combination of numbers and letters that represent binary digits

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Programming Languages…a wee-bit newer

What is assembly language? Instructions made

up of symbolic instruction codes, meaningful abbreviations and codes

Source program contains code to be converted to machine language

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Programming Languages…1960’s until now

What is COBOL? COmmon Business-Oriented Language

Designed for business applications

English-like statements make code

easy to read, write, and maintain

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Programming Languages…many more todayWhat are C, C++, C#, Visual Basic, Java, JavaScript,

Perl, PerlScript, PHP, Ruby on Rails, Cold Fusion…

Powerful languages

Requires professional programming skills

(or at least training of yourself)

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Programming Languages

What is a compiler? A program

(software) that converts the entire source program into machine language before executing it

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Programming Languages

What is an interpreter? A program that

translates and executes one program code statement at a time

Does not produce an object program

Browsers do this!(For example, Firefox or Internet Explorer)

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Programming Languages…many, many more

What are other available programming languages?

ALGOLALGOLALGOLALGOLADAADAADAADA APLAPLAPLAPL

BASICBASICBASICBASIC HYPERTALKHYPERTALKHYPERTALKHYPERTALKFORTRANFORTRANFORTRANFORTRANFORTHFORTHFORTHFORTH

LISPLISPLISPLISP MODULA-2MODULA-2MODULA-2MODULA-2LOGOLOGOLOGOLOGO

PASCALPASCALPASCALPASCAL PROLOGPROLOGPROLOGPROLOGPL/1PL/1PL/1PL/1PILOTPILOTPILOTPILOT

SMALLTALKSMALLTALKSMALLTALKSMALLTALK

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Programming Languages

What is an application generator? Program that creates source code or

machine code from a specification Consists of a report writer, a form, and

menu generator

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Programming Languages

What is HTML (Hypertext Markup Language)?

Used to create Web pages

Source Code: WYSIWYG(“wiz-e-wig”)What You See is What You Get:

View -> Source

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Programming Languages

What is a scripting language? Programming language used to allow Web

pages to be more “powerful” (do more things)

Examples: JavaScript VBScript Perl

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Programming Languages

What is dynamic HTML (DHTML)?

Enhanced version of HTML which allows developers to include more graphical interest and interactivity on Web pages

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Programming Languages

What are XML and WML?

XML XML (Extensible Markup Language)(Extensible Markup Language)

allows developers to create customized tags

WMLWML (Wireless Markup Language) (Wireless Markup Language)

allows developers to design pages specifically for microbrowsers

Many PDAs and smart phones use WML as their

markup language

Server sends entire record to client, enabling client to do much of processing without

going back to the server

<LastName>Norman</LastName><FirstName>Ronald</FirstName><College>Grossmont</College><OfficePhone>619-644-7515</OfficePhone>

Office 2007 default documentFormat is XML: .docx, .xlsx, .pptx

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Programming Languages

What is Web page authoring software? Creates sophisticated Web pages without

using HTML This software generates (creates) the

HTML code for you

Examples of Web page authoring

software

Companies on the Cutting Edge

Video: Electronic Arts Going Mobile

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