Syzztem anaalysus

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PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd Edition

Copyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 1

Systems Analysis and Systems Analysis and DesignDesign

Alan Dennis, Barbara Haley Wixom, and Roberta RothJohn Wiley & Sons, Inc.

Slides by Candace S. GarrodRed Rock Community College

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd Edition

Copyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 2

Moving into DesignMoving into Design

Chapter 8

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 3

Key Definitions

Design phaseDecide how to build the systemCreate system requirements that describe technical details for building the system

System specificationFinal deliverable from design phaseConveys exactly what system the design team will implement during the implementation phase

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 4

Transition from Requirement to Design

Influences on the Acquisition StrategySelecting a Design StrategySelecting a System Acquisition StrategySelecting a System Acquisition StrategyDeveloping an Alternative MatrixDeveloping an Alternative MatrixDeveloping an Alternative Matrix

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 5

Classical Design Mistakes

Reducing design timeFeature creepSilver bullet syndromeSwitching tools in mid-project

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 6

Design Strategies

Custom development (build from scratch) in-housePurchase software package (and customize it)Outsource development to third party

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 7

Custom Development

PROS

Allows flexibilityand creativity

Consistent with existingtechnology and standards

Builds technical skills and functional knowledge in-house

CONS

Requires significant timeand effort

May exacerbate existingbacklogs

May require missing skills

Often costs more

Often takes more calendartime

Risk of project failure

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 8

Packaged SoftwareAvailable for many common business needsTested, proven; cost and time savingsRarely a perfect fit with business needsMay allow for customization

Manipulation of system parametersChanging way features workSynchronizing with other application interfaces

May require workarounds

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 9

Systems Integration

Building systems by combining packages, legacy systems, and custom piecesIntegrating data is the key

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 10

Outsourcing

Hiring an external vendor, developer, or service providerMay reduce costs or add valueRisks include possibly

Losing confidential informationLosing control over future developmentLosing learning opportunities

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 11

Outsourcing Contracts

Time and arrangementsFixed-priceValue-added

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 12

Outsourcing Guidelines

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd Edition

Copyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 13

INFLUENCES ON THE INFLUENCES ON THE ACQUISTION STRATEGYACQUISTION STRATEGY

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 14

Selecting a Design Strategy

Consider each of the following when deciding what strategy to use:

Business needIn-house experienceProject skillsProject managementTime frame

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 15

Selecting a System Acquisition Strategy

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd Edition

Copyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 16

SELECTING AN SELECTING AN ACQUISITION STRATEGYACQUISITION STRATEGY

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 17

Developing an Alternative Matrix

What tools and technologies are needed for a custom development project?What vendors make products that address the project needs?What service providers would be able to build this application if outsourced?

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 18

Developing an Alternative Matrix

Combine several feasibility analyses into one matrixInclude technical, budget, and organizational feasibilitiesAssign weights to indicate the relative importance of the criteriaAssign scores to indicate how well the alternative meets the criteria

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 19

Developing an Alternative Matrix

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 20

Your Turn

If your university were investing in an on-line registration system, would you recommend --

Building it in-house? Buying a package? Outsourcing the project?

What is the basis for your recommendation?

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 21

Summary Slide

System Design Phase – transitioning from requirements to designDesign all the elements of the systemFirst Task – determine the system acquisition strategy

Custom developmentPurchase software packageOutsource

Use Alternatives Matrix to structure the system acquisition decision

PowerPoint Presentation for Dennis, Wixom, & Roth Systems Analysis and Design, 3rd EditionCopyright 2006 © John Wiley & Sons, Inc. All rights reserved.8 - 22

Copyright © 2006 John Wiley & Sons, Inc.

All rights reserved. Reproduction or translation of this work beyond that permitted in Section 117 of the 1976 United States Copyright Act without the express written permission of the copyright owner is unlawful. Request for further information should be addressed to the Permissions Department, John Wiley & Sons, Inc. The purchaser may make back-up copies for his/her own use only and not for redistribution or resale. The Publisher assumes no responsibility for errors, omissions, or damages, caused by the use of these programs or from the use of the information contained herein.