Week-6 1 Developing IS

Developing Information SystemsSystem Analysis & Design (1)

Mohammed MisbhauddinKing Faisal UniversitySpring 2013

Where do systems come from?

• Initiators: System Owners & System Users

• Why:• Problem – situation that prevents the organization from achieving its objectives

• Opportunity – chance to improve the organization

• Directive - a new requirement by • Management• Government• some external influence.

System Analysis & Design (I) - Misbhauddin

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PIECES Framework

• Framework to categorize the problems that initiate system building

• Typically to correct or improve


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PerformanceInformationEconomicsControlEfficiencyService

ProjectsSystem Analysis & Design (I) - Misbhauddin

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Projects

Planned Unplanned

IS Strategy Plan• Long-term value

Business ProcessRedesign

• Eliminate redundancy• Improve Efficiency

Problem DirectiveOpportunity

Unplanned Projects

ProjectProblemOpportunityDirective

Review

Steering Committee

Funds Staff

Approved

Backlogged

DevelopmentYes

No

Resource Available


FAST Methodology

Framework for the Application of Systems Thinking (FAST)

ProjectInitiation

SystemAnalysis

SystemDesign

SystemImpl.

Scope DefinitionProblem Analysis

Requirement AnalysisLogical Design

Decision AnalysisPhysical Design & Integration

Construction & TestingInstallation & Delivery

System Analysis Transition Phase

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System Analysis & Design (I) - MisbhauddinFAST Workflow

Business Community

Scope Definition

Problem Analysis

Requirement Analysis

Decision Analysis

Logical Design

Physical Design &

Integration

Installation &

Delivery

Construction &

Testing

ProblemsOpportunitiesDirectives Problem Statement

ScopeVision

ImprovementObjectives

RequirementsStatement

Logical Design

System Proposal

App. Arch.

Logical Design

Design Specs.Prototypes

Functional SystemTraining Manuals Documentati

on

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FAST Workflow – cont’d

Business Community

Installation &

Delivery

System Operation

& Maintenanc

e

Operational System

Post-Audit Review

Working Business Solution

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1. Scope DefinitionSystem Analysis & Design (I) - Misbhauddin 8

ProblemDirectivesOpportunities

System OwnersProject ManagersSystem Analysts

Scope Statement

Is the problem worth looking at?

Catalog & Categorize the problem (PIECES)Problem Statement

How big the project is?Establish base scopeAvoid Scope Creep

Project StaffingEstimate BudgetSchedule Tasks

Feasibility Check

Statement of WorkContract / Agreement

GO

NO-GO

Constraints

2. Problem AnalysisSystem Analysis & Design (I) - Misbhauddin 9


Documentation

If (benefit(solution) > cost (new-system)){

“AS-IS” Business ModelInefficienciesBottlenecksOther Issues

TerminologyHistoryCultureNuances Feasibility Check

System Improvement ObjectivesGrading Criteria

Cancel

Reduce/Expand

System Users

ProblemScope

Approved

Not worth Solving

Budget & ScheduleModification

3. Requirement AnalysisSystem Analysis & Design (I) - Misbhauddin 10

Project ManagersSystem Analysts

User Needs / Requirements

What capabilities should the new system provide?What data must be captured and stored?What performance level is expected?

Assign Priority

InterviewsQuestionnairesMeetings

Business Requirements Statement

System Users

Improvement Objectives

Re-scopingVersion Release

Priority

Challenge:Does each requirement contribute to meeting one or more system improvement objectives?

4. Logical DesignSystem Analysis & Design (I) - Misbhauddin 11


System ModelsTranslate Business Requirements into System Models

Methodology (# of models)

Logical Design

System Users

Business Requirements Statement

Prescriptive AgileStructured Analysis & DesignInformation EngineeringRational Unified Process

Rapid Application DevelopmentExtreme ProgrammingAvoids Analysis Paralysis

“Technology – independent”

5. Decision AnalysisSystem Analysis & Design (I) - Misbhauddin 12


How much to be automated by IT?Purchase or Build (Make vs. Buy)?Intranet based or Web-based?

System ProposalApplication Architecture

System Users

Logical Design

Step 1: Identify Candidate Technical Solutions

Step 2: Analyze solutions for feasibility

Step 3: Recommend a SolutionFeasibility Check

Reject

Reduced ScopeApproved

Technical Feasibility: Do we have the technical expertise?Operational Feasibility: Will it fulfill user requirements?Economic Feasibility: Is it cost-effective?Schedule Feasibility: Can it be implemented on time?Risk Feasibility: What is the probability of success?

6. Physical Design & IntegrationSystem Analysis & Design (I) - Misbhauddin 13


Physical Models

How technology will be used in the new system? Philosophies

Physical Design & Spec.Design Prototype

System Users

Logical DesignApplication Architecture

Design by Specification Design by Prototyping

Physical System ModelsDetailed Specs.

Prototype – Incomplete but Functional

System Integration Concerns

System Designers Feasibility Check

GO

NO-GOOver BudgetBehind Schedule

7. Construction & TestingSystem Analysis & Design (I) - Misbhauddin 14

System UsersProject ManagersSystem Analysts

Purpose 1. Build & test system that fulfills business requirements 2. Implement interfaces between new & existing system

Functional System

System Builders

Testing Individual System Components Overall System

Databases: OLTP, ODS, DWCommercial S/W Packages Custom-Built SoftwareUser & System Interfaces:

Physical Design & Spec.Design Prototype

MiddlewareSystem

Final Documentation

Training ManualsHelp Desk SupportInstructions

8. Installation & DeliverySystem Analysis & Design (I) - Misbhauddin 15

System Users


Install System from Development Env. To User Env.

Operational SystemPost-Audit Review

System Builders

TransitionAbrupt Cutover

Parallel OperationConversionPlan

Functional System

Train

OperationalSystem

Feedback

Measure Success of the Completed Project

Post-AuditReview

System Operation & Maintenance

• System Support• Assisting Users (Customer Care)• Fixing Defects• Recovering the System (in case of System

Failure)• Adapting to new requirements


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Conclusion

• System Development Process

• PIECES Framework for Problem Identification

• FAST Phases – A Software Development Process


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Announcement

• Reminder• Quiz-1 (Wednesday 09/10/2013)• Material: Chapters 1• Duration: 10 mins.• Starts-at: 08:30am (No extra time for late-comers)


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Week-6 1 Developing IS

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