12. ALTERNATIVE SYSTEMBUILDING METHODS
12.1
INFORMATION SYSTEM
BUSINESS
CHALLENGE
MANAGEMENT
INFORMATION
INFORMATION
BUSINESS
SYSTEM
SOLUTIONS
TECHNOLOGY
DETERMINING SYSTEM DEVELOPMENT
STRATEGY
ORGANIZATION
12.2
CONTROLLING DEVELOPMENT
OUTSIDE INFO SYSTEM DEPARTMENT
FITS FIRM’S INFO ARCHITECTURE &
STRATEGIC PLAN
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
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
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
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
*
STEPS IN PROTOTYPING
•
•
•
•
IDENTIFY USER’S REQUIREMENTS
DEVELOP PROTOTYPE
USE PROTOTYPE
REVISE & ENHANCE PROTOTYPE
BEST FOR DESIGN OF END-USER
INTERFACE: How End-user Interacts
With System
*
12.7
APPLICATION SOFTWARE PACKAGES
REWRITTEN, PRECODED APPLICATION
SOFTWARE, COMMERCIALLY AVAILABLE
FOR SALE OR LEASE
• GEARED TO COMMON REQUIREMENTS
• CUSTOMIZATION: Modification of
Software to Meet Organization’s Needs
• MUST WEIGH COSTS / BENEFITS
*
12.8
SELECTED EXAMPLES OF APPLICATION
PROGRAMS
12.9
ACCOUNTS PAYABLE/RECEIVABLE; ARCHITECTURAL
DESIGN; BANKING; CHECK PROCESSING; COMPUTERAIDED-DESIGN; DOCUMENT IMAGING; ENGINEERING; EMAIL; 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
*
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
CUSTOMIZATION
MODIFYING SOFTWARE PACKAGE
TO MEET ORGANIZATION’S UNIQUE
REQUIREMENTS
WITHOUT DESTROYING INTEGRITY
OF PACKAGE
RAISES DEVELOPMENT COSTS
*
12.11
EFFECTS OF CUSTOMIZING SOFTWARE ON
TOTAL IMPLEMENTATION COSTS
TOTAL IMPLEMENTATION
COSTS
10
8
6
4
2
0
0.5
1
2
3
4
5
% LINES OF CODE CONVERTED
12.12
REQUEST FOR PROPOSAL (RFP)
Detailed list of Questions
Submitted to Vendors
to Determine if Vendor’s Product
meets Organization’s Specific
Requirements
*
12.13
PACKAGE EVALUATION CRITERIA
•
•
•
•
•
•
•
•
•
•
FUNCTIONS INCLUDED
FLEXIBILITY
USER FRIENDLINESS
HARDWARE & SOFTWARE RESOURCES
DATABASE/FILE CHARACTERISTICS
INSTALLATION EFFORTS
MAINTENANCE
DOCUMENTATION
VENDOR QUALITY
COST
*
12.14
APPLICATION PACKAGE DEVELOPMENT CYCLE
•
•
•
•
SYSTEMS ANALYSIS
SYSTEMS DESIGN
PROGRAMMING, TESTING, CONVERSION
PRODUCTION & MAINTENANCE
*
12.15
SYSTEMS ANALYSIS:
• Identify Problem; User
Requirements; Alternatives; Vendors
• Package vs. In-House Development
• Evaluate Packages
• Select Package
*
12.16
SYSTEMS DESIGN:
•
•
•
•
•
Tailor Package Features
Train Technical Staff
Prepare Physical Design
Customize Package Design
Organizational Procedures
*
12.17
PROGRAMMING, TESTING, CONVERSION:
•
•
•
•
•
•
•
Install Package
Implement Modifications
Design Program Interfaces
Documentation
Convert to Package System
Test System
Train Users on Package
*
12.18
PRODUCTION & MAINTENANCE:
• Correct Problems
• Install Updates, Enhancements to
Package
*
12.19
END-USER DEVELOPMENT
END-USERS DEVELOP INFORMATION
SYSTEM
WITH LITTLE HELP FROM
TECHNICAL SPECIALISTS
USING 4th GENERATION TOOLS
*
12.20
END-USER DEVELOPMENT
STRENGTHS:
• INCREASED PRODUCTIVITY USING 4th
GENERATION TOOLS
• QUERY LANGUAGES
• GRAPHICS
• REPORT GENERATORS
• APPLICATION GENERATORS
• SHORT DEVELOPMENT TIMES
*
12.21
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
*
END-USER DEVELOPMENT
MANAGEMENT BENEFITS:
• IMPROVED REQUIREMENTS
DETERMINATION
• INCREASED USER INVOLVEMENT &
SATISFACTION
• DEVELOPMENT CONTROLLED BY USERS
• REDUCED APPLICATION BACKLOG
*
12.23
END-USER DEVELOPMENT
MANAGEMENT PROBLEMS:
• INSUFFICIENT REVIEW / ANALYSIS
• LACK OF STANDARDS & CONTROLS
• UNCONTROLLED DATA
• PROLIFERATION OF “PRIVATE” INFO
SYSTEMS
*
12.24
END-USER DEVELOPMENT
INFORMATION CENTER:
SPECIAL FACILITY WITHIN ORGANIZATION
PROVIDES TRAINING, SUPPORT FOR
END-USER COMPUTING
*
12.25
OUTSOURCING
CONTRACTING:
• COMPUTER CENTER OPERATIONS
• TELECOMMUNICATIONS NETWORKS
• APPLICATION DEVELOPMENT
TO EXTERNAL VENDORS
*
12.26
ADVANTAGES OF OUTSOURCING:
•
•
•
•
•
•
•
ECONOMY
SERVICE QUALITY
PREDICTABILITY
FLEXIBILITY
MAKING FIXED COSTS VARIABLE
FREEING UP HUMAN RESOURCES
FREEING UP CAPITAL
*
12.27
DISADVANTAGES OF OUTSOURCING:
• LOSS OF CONTROL
• VULNERABILITY OF STRATEGIC
INFORMATION
• DEPENDENCY
*
12.28
PENALTY FOR PROBLEMS
REWARDS & PENALTIES OF OUTSOURCING
HIGH
LOW
12.29
AIRLINE
RESERVATIONS
PAYROLL
PLANT
SCHEDULING
HIGH
OUTSOURCING
POTENTIAL
ENGINEERING
ANALYSIS TOOLS
CAFETERIA
ACCOUNTING
REWARDS FOR EXCELLENCE
HIGH
12. ALTERNATIVE SYSTEMBUILDING METHODS
12.30