12. ALTERNATIVE SYSTEM-BUILDING METHODS

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12. ALTERNATIVE SYSTEM-BUILDING METHODS
12.1
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DETERMINING SYSTEM DEVELOPMENT STRATEGY CONTROLLIN
G DEVELOPMENT OUTSIDE INFO SYSTEM DEPARTMENT FITS
FIRMS INFO ARCHITECTURE STRATEGIC PLAN
12.2
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SYSTEM LIFECYCLE

• PROJECT DEFINITION Is There a Problem? Can it be
  Solved with a Project?
• SYSTEM STUDY Analyze problems in Existing
  Systems Define Objectives Evaluate Alternatives
• DESIGN Logical Physical Specifications for
  Systems Solution
• PROGRAMMING Develop Software Code

12.3
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SYSTEM LIFECYCLE

• INSTALLATION Construct, Test, Train, Convert to
  New System
• POSTINSTALLATION On-going Evaluation,
  Modifications for Improvement to meet New
  Requirements
• NECESSARY FOR LARGE, COMPLEX SYSTEMS
  PROJECTS

12.4
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SYSTEM LIFECYCLE

• CAN BE COSTLY, TIME CONSUMING
• MAY ENCOURAGE FREEZING SPECIFICATIONS EARLY IN
  DEVELOPMENT
• MAY NOT BE SUITABLE FOR SMALL, LESS STRUCTURED
  SYSTEMS

12.5
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PROTOTYPING

• PROCESS OF BUILDING EXPERIMENTAL SYSTEM TO
  DEMONSTRATE, EVALUATE APPROACH USERS REFINE
  NEEDS
• PROTOTYPE Preliminary working version of
  Information System for Demonstration, Evaluation
  Purposes
• ITERATIVE PROCESS

12.6
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STEPS IN PROTOTYPING

• IDENTIFY USERS REQUIREMENTS
• DEVELOP PROTOTYPE
• USE PROTOTYPE
• REVISE ENHANCE PROTOTYPE
• BEST FOR DESIGN OF END-USER INTERFACE How
  End-user Interacts With System

12.7
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APPLICATION SOFTWARE PACKAGES

• REWRITTEN, PRECODED APPLICATION SOFTWARE,
  COMMERCIALLY AVAILABLE FOR SALE OR LEASE
• GEARED TO COMMON REQUIREMENTS
• CUSTOMIZATION Modification of Software to Meet
  Organizations Needs
• MUST WEIGH COSTS / BENEFITS

12.8
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SELECTED EXAMPLES OF APPLICATION PROGRAMS

• ACCOUNTS PAYABLE/RECEIVABLE ARCHITECTURAL
  DESIGN BANKING CHECK PROCESSING
  COMPUTER-AIDED-DESIGN DOCUMENT IMAGING
  ENGINEERING E-MAIL FINANCIAL CONTROL
  FORECASTING FORMS DESIGN GRAPHICS HOTEL
  MANAGEMENT HUMAN RESOURCES INSTALLMENT LOANS
  INVENTORY CONTROL JOB COSTING/SCHEDULING LIFE
  INSURANCE MAILING LABELS MATHEMATICAL /
  STATISTICAL MODELING ORDER ENTRY PAYROLL
  PROCESS CONTROL REAL ESTATE MANAGEMENT SALES
  DISTRIBUTION SAVINGS SYSTEMS STOCK MANAGEMENT
  TAX ACCOUNTING UTILITY CONTROLS WORD PROCESSING

12.9
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USE APPLICATION PACKAGES

• 1. Where Functions are Common to many Companies
• 2. Where In-House Resources are Scarce
• 3. When Microcomputer Applications are being
  Developed for End Users

12.10
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CUSTOMIZATION

• MODIFYING SOFTWARE PACKAGE
• TO MEET ORGANIZATIONS UNIQUE REQUIREMENTS
• WITHOUT DESTROYING INTEGRITY
• OF PACKAGE
• RAISES DEVELOPMENT COSTS

12.11
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EFFECTS OF CUSTOMIZING SOFTWARE ON TOTAL
IMPLEMENTATION COSTS
10
8
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TOTAL IMPLEMENTATION
COSTS
4
2
0
0.5
1
2
3
4
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LINES OF CODE CONVERTED
12.12
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REQUEST FOR PROPOSAL (RFP)

• Detailed list of Questions
• Submitted to Vendors
• to Determine if Vendors Product meets
  Organizations Specific Requirements

12.13
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PACKAGE EVALUATION CRITERIA

• FUNCTIONS INCLUDED
• FLEXIBILITY
• USER FRIENDLINESS
• HARDWARE SOFTWARE RESOURCES
• DATABASE/FILE CHARACTERISTICS
• INSTALLATION EFFORTS
• MAINTENANCE
• DOCUMENTATION
• VENDOR QUALITY
• COST

12.14
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APPLICATION PACKAGE DEVELOPMENT CYCLE

• SYSTEMS ANALYSIS
• SYSTEMS DESIGN
• PROGRAMMING, TESTING, CONVERSION
• PRODUCTION MAINTENANCE

12.15
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SYSTEMS ANALYSIS

• Identify Problem User Requirements
  Alternatives Vendors
• Package vs. In-House Development
• Evaluate Packages
• Select Package

12.16
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SYSTEMS DESIGN

• Tailor Package Features
• Train Technical Staff
• Prepare Physical Design
• Customize Package Design
• Organizational Procedures

12.17
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PROGRAMMING, TESTING, CONVERSION

• Install Package
• Implement Modifications
• Design Program Interfaces
• Documentation
• Convert to Package System
• Test System
• Train Users on Package

12.18
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PRODUCTION MAINTENANCE

• Correct Problems
• Install Updates, Enhancements to Package

12.19
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END-USER DEVELOPMENT

• END-USERS DEVELOP INFORMATION SYSTEM
• WITH LITTLE HELP FROM
• TECHNICAL SPECIALISTS
• USING 4th GENERATION TOOLS

12.20
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END-USER DEVELOPMENT

• STRENGTHS
• INCREASED PRODUCTIVITY USING 4th GENERATION TOOLS
• QUERY LANGUAGES
• GRAPHICS
• REPORT GENERATORS
• APPLICATION GENERATORS
• SHORT DEVELOPMENT TIMES

12.21
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END-USER DEVELOPMENT

• WEAKNESSES
• RELATIVELY INEFFICIENT
• SLOW TRANSACTION PROCESSING
• MAY CARRY HIGH COST
• LARGE FILES CAN DEGRADE PERFORMANCE
• NONPROCEDURAL APPROACH MAY HAMPER LOGIC
  UPDATING REQUIREMENTS

12.22
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END-USER DEVELOPMENT

• MANAGEMENT BENEFITS
• IMPROVED REQUIREMENTS DETERMINATION
• INCREASED USER INVOLVEMENT SATISFACTION
• DEVELOPMENT CONTROLLED BY USERS
• REDUCED APPLICATION BACKLOG

12.23
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END-USER DEVELOPMENT

• MANAGEMENT PROBLEMS
• INSUFFICIENT REVIEW / ANALYSIS
• LACK OF STANDARDS CONTROLS
• UNCONTROLLED DATA
• PROLIFERATION OF PRIVATE INFO SYSTEMS

12.24
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END-USER DEVELOPMENT

• INFORMATION CENTER
• SPECIAL FACILITY WITHIN ORGANIZATION
• PROVIDES TRAINING, SUPPORT FOR
• END-USER COMPUTING

12.25
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OUTSOURCING

• CONTRACTING
• COMPUTER CENTER OPERATIONS
• TELECOMMUNICATIONS NETWORKS
• APPLICATION DEVELOPMENT
• TO EXTERNAL VENDORS

12.26
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ADVANTAGES OF OUTSOURCING

• ECONOMY
• SERVICE QUALITY
• PREDICTABILITY
• FLEXIBILITY
• MAKING FIXED COSTS VARIABLE
• FREEING UP HUMAN RESOURCES
• FREEING UP CAPITAL

12.27
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DISADVANTAGES OF OUTSOURCING

• LOSS OF CONTROL
• VULNERABILITY OF STRATEGIC INFORMATION
• DEPENDENCY

12.28
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REWARDS PENALTIES OF OUTSOURCING
HIGH
AIRLINE RESERVATIONS
PAYROLL
PLANT SCHEDULING
PENALTY FOR PROBLEMS
HIGH OUTSOURCING POTENTIAL
ENGINEERING ANALYSIS TOOLS
CAFETERIA ACCOUNTING
LOW
HIGH
REWARDS FOR EXCELLENCE
12.29
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12. ALTERNATIVE SYSTEM-BUILDING METHODS
12.30