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Objectives of This Chapter
Understand outsourcing
Describe techniques available for system development
Describe each step involve in the Systems Development Life Cycle (SDLC)
Identify the activities involved in the implementation of new information systems.
4
Outsourcing ForcesGlobalization, new
competitors.
Shorter product life-cycles,mass customization.
Rapidly changing markets,flexible manufacturing.
Pressure on profits.
Need to focus on increasingrevenues and decreasingfixed/semi-fixed costs.
Need for flexibilityand responsiveness.
Outsourcenon-revenuegenerate functions(staff/operations)
Desire to minimize amountof management time devoted to non-revenue generating functions.
Economies of Scale- leverage expertise and methodologies.- invest in expensive technologies (state-of-the-art)- process-oriented approach
Economies of ScopeWant one vendor toprovide multiplefunctions.
Cost cutting, staff cuts,loss of middle management.
Big Outsourcing Vendors& Big 6 Firms
5
Outsourcing Evaluation
Specialized Talent Needed
Complex Market Structure
Security & ControlLevel ofTechnology
Cost of reachingstate of the art
Fixed Costs
When any of these characteristics increases (moves outwards), there is less reason to use outsourcing.
6
Benefits of Outsourcing
Provide business solution Asset utilization Access to greater expertise and more advanced technology Lower Cost Improve development time Eliminate of peaks and valley usage Facilitation of downsizing
7
Risks of Outsourcing
Inflexibility Loss of control Reduced competitive advantage locked-in system Unfulfilled goals
9
The Systems Approach The Systems Approach to Problem Solvingto Problem Solving
The Systems Approach The Systems Approach to Problem Solvingto Problem Solving
The Systems Approach to Problem Solving Involves a Five-Step Process
Each Step Requires Managers and End Users to Ask Questions designed to Identify Areas of a Problem Clearly.
10
The Systems Approach The Systems Approach to Problem Solvingto Problem Solving
The Systems Approach The Systems Approach to Problem Solvingto Problem Solving
Designthe Solution
Designthe Solution
Definethe Problem
Definethe Problem
DevelopAlternativeSolutions
DevelopAlternativeSolutions
Selectthe Solution
Selectthe Solution
Implementthe SolutionImplement
the Solution
Mo
nit
or
and
Ev
alu
ate
Re
sult
s
11
Evaluating the System Evaluating the System Components of a Sales Components of a Sales
SystemSystem
Evaluating the System Evaluating the System Components of a Sales Components of a Sales
SystemSystemThe Following Slide Illustrates the
Sales Function of a Business as a System.The Following Slide Illustrates the
Sales Function of a Business as a System.
Notice How Questions Posed at Each Stagein the Process Attempt to Identify
and Isolate the Causes of the Problem.
Notice How Questions Posed at Each Stagein the Process Attempt to Identify
and Isolate the Causes of the Problem.
12
A Systems Context ExampleA Systems Context ExampleA Systems Context ExampleA Systems Context Example
Out-of-DateSales
Procedures?
InadequateSellingEffort
?
PoorSales
Performance?
PoorSales
Management?
IncorrectSales
Information?
Feedback
Input Processing Output
Control
13
Once a poor system/process is identified, the next step is to
develop a new system or modify the existing system
14
System Development Difficulties
Most problems are so large that they have to be split into smaller pieces
Each piece end up does not fit back together
It was hard to coordinate and control the various programmers and analysts, so there are many duplicated efforts
The initial development team leave the company
15
To reduce these difficulties, several techniques are adopted
to control the system development effort
16
Techniques for System Development
System Development Life Cycle (SDLC)System Development Life Cycle (SDLC)
PrototypingPrototyping
Joint Application Development (JAD) Joint Application Development (JAD)
Object-Oriented DevelopmentObject-Oriented Development
End User DevelopmentEnd User Development
17
Systems Development Life Cycle (SDLC)
1. Systems Investigation/Planning (Feasibility Study)
2. Systems Analysis
3. Systems Design
4. Systems Implementation
5. System Maintenance
18
The Systems Development The Systems Development CycleCycle
The Systems Development The Systems Development CycleCycle
Systems ImplementationProduct:
Operational System
Systems ImplementationProduct:
Operational System
Systems InvestigationProduct:
Feasibility Study
Systems InvestigationProduct:
Feasibility Study
Systems AnalysisProduct:
Functional Requirements
Systems AnalysisProduct:
Functional Requirements
Systems DesignProduct:
System Specifications
Systems DesignProduct:
System Specifications
Systems MaintenanceProduct:
Improved System
Systems MaintenanceProduct:
Improved System
Understand theBusiness
Problem orOpportunity
Develop anInformation
SystemSolution
Implementthe
SystemSolution
19Existing System
Systems Maintenance: Incremental changes
Feasibility &Planning
SystemsAnalysis
SystemsDesign
SystemsImplementationProblems &
ImprovementsNew System
Proposal
Goals & plans
Business requirements
Technical Design
problemsrevisions problems revisions
Systems Development Life Cycle
21
Feasibility Study
A feasibility study is a quick examination of the problems, goals, and expected cost of the system
In other words, to determine the scope of the project to gain a better idea of the costs, benefits, and objectives
A planned schedule is also created to keep the project on track and to evaluate the progress of the MIS team
23
Feasibility StudyFeasibility StudyFeasibility StudyFeasibility Study
OrganizationalFeasibility
TechnicalFeasibility
EconomicFeasibility
OperationalFeasibility
24
Feasibility Study
Organizational FeasibilityOrganizational Feasibility• Is the project aligned with the organization’s goal?Is the project aligned with the organization’s goal?
Economic FeasibilityEconomic Feasibility• Is the project cost-effective?Is the project cost-effective?
Technical FeasibilityTechnical Feasibility• Does the technology exist and does the firm have the staff to Does the technology exist and does the firm have the staff to
make the technology work?make the technology work?
Operational FeasibilityOperational Feasibility• Will the project improve the operation of the firm?Will the project improve the operation of the firm?
25
Systems Project Proposals
Feasibility Factors• Organizational
• Economic
• Technical
• Operational
Types of Systems• Strategic Systems (necessary)
• Productivity Improvement (optional)
26
Once the project has been shown to be feasible and it is approved, the next step is to
begin on the full-fledged system analysis
29
Systems AnalysisSystems Analysis
KeyAreas ofSystemsAnalysis
OrganizationalOrganizational
FunctionalRequirements
FunctionalRequirements
PresentSystemPresentSystem
30
System Analysis
The technique is to break the system into pieces.• Smaller pieces are easier to understand and to explain
to the others
• Each piece can be assigned to a different team
Diagrams are often created to illustrate the system
A variety of tools are available to enhance the system analysis
31
Visual Table of Contents (VTOC)
Customer Order Entry
Enter Salesperson Data
Enter/Change Customer Data
Enter Items Ordered
Review and Print Forms
Look up Item Numbers
Check Inventory Status
Special Orders
Customer Order Copy
Shipping List
Back Order List
32
System Analysis
At this stage, users should verify that • the system contains all of the desired functions,
• the system is easy to understand, and
• common tasks do not require an excessive number of keystroke
At the end of the analysis phase, the MIS team will have a complete description of the business requirement.
34
Systems DesignSystems DesignSystems DesignSystems Design
DataDesignData
Design
UserInterfaceDesign
UserInterfaceDesign
ProcessDesign
ProcessDesign
35
System DesignSystem Design
The objective of system design is to describe the The objective of system design is to describe the new system as a collection of modules or subsystemsnew system as a collection of modules or subsystems
By subdividing the total project, each portion can be By subdividing the total project, each portion can be given to each developergiven to each developer
Once the designer has created base modules and Once the designer has created base modules and sample inputs and outputs, the users are invited to a sample inputs and outputs, the users are invited to a structured walkthroughstructured walkthrough
36
Structured Walkthrough
A structured walkthrough is a review process A structured walkthrough is a review process where the objective is to reveal:where the objective is to reveal:• problemsproblems
• inaccuraciesinaccuracies
• ambiguitiesambiguities
• omissions in the system design omissions in the system design
before the program code is finalizedbefore the program code is finalized
37
System DesignSystem Design
In term of physical design, the evaluation can be classified into:
• Hardware Evaluation
• Software Evaluation
38
Hardware EvaluationHardware EvaluationHardware EvaluationHardware Evaluation
HardwareEvaluation
Factors
SupportSupport CostCost
ReliabilityReliabilityEnvironmentalRequirements
EnvironmentalRequirements
TechnologyTechnology
ConnectivityConnectivity CompatibilityCompatibility
PerformancePerformance
39
Software EvaluationSoftware EvaluationSoftware EvaluationSoftware Evaluation
EfficiencyEfficiency
FlexibilityFlexibility
SecuritySecurity
LanguageLanguage
DocumentationDocumentation
HardwareHardware
Other FactorsOther Factors
SoftwareEvaluationFactors
SoftwareEvaluationFactors
40
Suite of Products - Examples
Microsoft Corporation– Word – Excel– PowerPoint
Lotus Development Corporation– AmiPro– Lotus 1-2-3– Freelance
Novell/Borland– WordPerfect– Borland– dBaseIV
41
Suite of Products Advantages
Integrated Document
Economies of Scale
Consolidated Training
Shared Files Across Group
42
Suite of Products Disadvantages
Choice Based upon Group Rather than Advantages of Individual Product
“Locked In” to Product Company
Difficulty in Matching Client Requirements
43
System Design
One of the difficulties in this stage is sometimes called “creeping elegance” • At the system is being built, analyst, programmers, and
users all want to include additional features
• The continual evolution causes additional delays
• Cost over budget
The output of this design stage consists of a complete technical specification of the new system
45
The Implementation ProcessThe Implementation ProcessThe Implementation ProcessThe Implementation Process
ConversionConversionSystemDocu-
mentation
SystemDocu-
mentation
End UserTrainingEnd UserTraining
Developmentand
Modification
Developmentand
ModificationAcquisitionAcquisition
ImplementationActivities
ImplementationActivities
46
System Implementation
System implementation involves installation and changeover from the previous system to the new one, including training users and making adjustments to the system
The major difficulties to this stage is how to deal with users’ resistance to changes• users are probably nervous about the change
• users might not want to learn the new thing
47
System Implementation Concerns
Involve Users• the users will get the system they need• the users will understand the system better and it will be easier
too use• the users contributions provide a sense of ownership
Education & Training• the users will be less nervous if they learn more about the system
Flexibility• simple things like being able to change the colors can be critical
to keeping users happy
48
Implementation Plans
Direct cutover• drop the old system when the new one starts
Parallel• the safest choice, both systems are operated at the same
time
Pilot/Phased• gradually install the new system (one store each time)
49
Implementation Options
old new
old
new
newnewnew
new
Direct cutover
Parallel
Pilot
new
Phased
olddept or component 1
dept or component 2
dept or component 3dept or component 4
store 1
store 2store 3
store 4
51
Software Maintenance
Computer systems are constantly changing
Hardware/Software upgrade
The pressure for change are so great that 80% of staff today are devoted to modifying existing programs
52
Stage Procedure Approx. Pct. Of Effort
Analysis Feasibility 5
Requirements 15
Conceptual Design 5
Design Physical Design 20
Programming 25
Procedure Develop. 10
Implementation 15
Maintenance & Review 5
SDLC EffortSDLC Effort
53
SDLC Advantages
Provide guidance and control Formality
• Easier to train and evaluate the progress. • Also ensure that steps are not skipped - such as user
approval documentation, and testing
Adhering to standard • It is easier to modify later
Ease of maintenance • The internal consistency and documentation make it easier
to modify
54
SDLC DisadvantagesSDLC Disadvantages
Increased costs
Lengthen the development time• A great deal of time is spent filling out forms and drawing
diagrams
Requires definitions up front• Users and managers need to know exactly what the system
should do long before the system is created
Rigid
57
CASE Tool
The main objective of CASE tool is to help a firm design and build systems faster
CASE tools help analysts draw and maintain several types of diagrams, including data flow diagrams
One drawback to CASE tools is that they are relatively expensive, both for:• cost of software
• cost of training
58
Components of Computer-Aided Systems Engineering includes:• workstations• central repository• numerous modeling tools• project management• Systems Development Life Cycle Support• Prototyping Applications• Software Design Features
CASE Tool
59
Computer-Aided Systems Computer-Aided Systems EngineeringEngineering
Computer-Aided Systems Computer-Aided Systems EngineeringEngineering
PlanningToolset
AnalysisToolset
DesignToolset
InformationIntegrator Workstation
Repositories
CodeGeneration
Toolset
DatabaseGeneration
Toolset
PublicInterface
ServerRepository
CASE
61
Common Steps of Prototyping
1. Talk with the users
2. Create roughly what the users want
3. Let users work with the prototype and then the users suggest changes
4. Make changes
5. Repeat steps 3 & 4 until the users are satisfied with the system or decides that the system is not worth pursuing
62
Build Initial Prototype
Use Prototype
Modify PrototypeRequest changes
New Version
MIS Designer User
Initial Interview
Process repeats until:
1) User is satisfied2) User and designer give up3) Formal system is built from prototype4) Need for application is removed5) Process never ends
Prototyping
63
The Prototyping ProcessThe Prototyping ProcessThe Prototyping ProcessThe Prototyping Process
Use and Maintainthe Accepted
System
Use and Maintainthe Accepted
System
Identify an EndUser's Information
Requirements
Identify an EndUser's Information
Requirements
DevelopInformation System
Prototype
DevelopInformation System
Prototype
Revise the Prototypeto Better Meet EndUser Requirements
Revise the Prototypeto Better Meet EndUser Requirements
Prototyping Cycle
Maintenance Cycle
64
Prototyping
Prototyping has been proposed as a method to use for systems that are not overly complex
The major advantage of prototyping is that the development time is much shorter than the SDLC
The drawback is the lack of formality and guideline: For example, if several users are involved, they might not agree on how the system should behave
65
Advantages of Prototyping
Better definition of user needs Higher user involvement and satisfaction Faster development time Fewer errors More opportunity for changes Lee costly
66
Disadvantages of Prototyping
Significant user time Less efficient use of system resources Incomplete systems development Inadequate tested and documented systems Negative behavior reactions Never ending development
67
Developing Systems with Teams
Developing systems is generally a team effort among MIS developers and business users. Groupware, CASE, and development tools are often used to facilitate communication and coordination.
69
JADJAD
A technique known as JAD was created to speed up the design stage
JAD use a Conceptual Systems Design Model which consist of• Data Flow Diagram• Entity Relationship Diagram• Decision Table• Screen Prototype• Decision Tree
70
Common Steps of JADCommon Steps of JAD
With JAD, the main system is designed in an intense three to five days workshop
By putting all of the decision makers in one room at the same time, conflicts are identified and resolved faster
The drawbacks are:• It requires getting everyone together at the same time for an
extended period of time• An effective facilitator is needed
72
An object can be anything from an icon on a computer to an accounting statement
Objects have sets of characteristics or attributes, and methods or operations that can be performed on objects
With objects, all functions are embedded in the definition of the object
Object-Oriented Development
73
Object Example
Object Classes
Customers
Name
Address
Phone
Change AddressAdd New Customer
Delete Customer
Commercial
Contact
Account Representative
Assign Account Rep Frequent
ContactAccount Representative
Year Started
Assign Account Rep
Individual
Object
Properties/Attributes
Methods/Functions
74
Object-Oriented Approach
Classes• Set of Objects that share common structure and behavior
Inheritance• Objects receive attributes and operations from other
objects• Add more attributes and operations of their own
Polymorphism• Ability of object to respond to and implement each object
75
Object-Oriented Steps
Identify Object Class
Identify Relationships
Identify Attributes
Determine Inheritance Relationships
Build Class Hierarchy
76
Object Example
Object Classes
Customers
Name
Address
Phone
Change AddressAdd New Customer
Delete Customer
Commercial
Contact
Account Representative
Assign Account Rep Frequent
ContactAccount Representative
Year Started
Assign Account Rep
Individual
Object
Properties/Attributes
Methods/Functions
77
When a certain event occurs, When a certain event occurs, data elements will be changed data elements will be changed
or added automaticallyor added automatically
Objects & Events Driven Systems
78
Objects & Events Driven Systems
Events Methods Objects
SaleRecord Sale
Update Inventory
Notify Customer Service
Inventory
Customers
Employees (commissions)
InventoryOrder/JIT
Notify Suppliers
Schedule Payment
Accounts & Ledgers
Suppliers
Shipping/Receiving
80
End-User Development
Users do all the development work themselves
The main advantage is the users get what they want
the end-user development become popular because• Increase waiting time for MIS personnel
• More powerful tools are available and easier to use
81
Advantages of End-user Development
User creation, control, and implementation Systems that meet user needs Timeliness Freeing up IS resource Versatility and ease of use
82
Risks ofEnd-user Development
Logic and development errors Inadequate tested applications Inefficient systems Poorly controlled and documented systems (hard to
modify by others) System incompatibilities Duplication of systems and data and wasted resources Increased costs (users’ time)
83
Project Management Skills PlanningPlanning
• States what should be doneStates what should be done• Estimates how long it will takeEstimates how long it will take• Estimates what it will costEstimates what it will cost
LeadingLeading• Adapts to dynamics of enterprise and deals with setbacksAdapts to dynamics of enterprise and deals with setbacks• Guides and induces people to perform at maximum abilitiesGuides and induces people to perform at maximum abilities
ControllingControlling• Monitors Progress Reports and Documented DeliverablesMonitors Progress Reports and Documented Deliverables• Compares Plans with ActualsCompares Plans with Actuals
OrganizingOrganizing• Staffs a Systems Project TeamStaffs a Systems Project Team• Brings together users, managers, and team membersBrings together users, managers, and team members
84
Choosing Methodologies
SDLC Prototyping JAD Objects End User
Control formal user joint standards user
Time frame long short medium any short
Users many one or two few varies one
MIS staff many one or two few split none
Trans./DSS Trans. DSS DSS both DSS
Interface minimal crucial crucial Windows crucial
Document.& Training vital weak limited in objects none
Integrity &Security vital weak limited in objects weak
Re-usability limited weak limited vital none
85
SDLC v.s. Object-Oriented
SDLC versus Object Oriented
0
10
20
30
40
50
60
Requirements Analysis Design Implementation
% t
ime
SDLC
Object Oriented
86
Unsuccessful Systems
Systems were developed which did not support business strategies and objectives.
Poor systems planning and inadequate project management.
Failure to define or understand user requirements.
Negligence in estimating costs and benefits of the systems project.
Creation of a myriad of design defects and errors.
87
Unsuccessful Systems
Acquisition of computers and software that no one needs or knows how to use.
Installation of incompatible or inadequate technology.
Negligence in implementing adequate controls.
Development of unstructured, unmaintainable software.
Inadequate implementation tasks.
88
Techniques and Activities Techniques and Activities used to Minimize End User used to Minimize End User
Resistance to ChangesResistance to Changes
89
Minimizing End User Minimizing End User Resistance to ChangeResistance to Change
Minimizing End User Minimizing End User Resistance to ChangeResistance to Change
StagesStages ActivityActivity GoalGoal
Pre-Implementation
Pre-Implementation
HumanDesignHumanDesign
MarketingMarketing
EducationEducation
Gather DataGather Data Determine Alternatives,Needed Resources, and Possible Roadblocks
Determine Alternatives,Needed Resources, and Possible Roadblocks
Study Automation and Establish Criteria for Its Human Design
Study Automation and Establish Criteria for Its Human Design
Eliminate Deterrents and Establish Incentives
Eliminate Deterrents and Establish Incentives
Develop and Implement Strategy for "Selling" Technical Systems
Develop and Implement Strategy for "Selling" Technical Systems
Introduce Technology So Workers "Buy and Own" the System
Introduce Technology So Workers "Buy and Own" the System
Educate Workers About the Demands of the New Technology
Educate Workers About the Demands of the New Technology
Reduce Stress and Increase ConfidenceReduce Stress and Increase Confidence
90
Minimizing End User Minimizing End User Resistance to ChangeResistance to Change
Minimizing End User Minimizing End User Resistance to ChangeResistance to Change
StagesStages ActivityActivity GoalGoal
TrainingTraining
DocumentationDocumentation
Develop and Implement Skills Growth ProgramDevelop and Implement Skills Growth Program
Develop Minimal CompetenceDevelop Minimal Competence
Develop & Distribute Adequate Documentation on How the System Works
Develop & Distribute Adequate Documentation on How the System Works
HumanCommunication
HumanCommunication
PostImplementation
PostImplementation
Establish and Maintain Open Channels of Communication
Establish and Maintain Open Channels of Communication
Create Opportunities for Dialogue with Users
Create Opportunities for Dialogue with Users
Evaluate Each Phase of the ProcessEvaluate Each Phase of the Process
Feedforward Results as Input to Next Technology Implementation
Feedforward Results as Input to Next Technology Implementation
Provide Easy Access and Effective Assistance
Provide Easy Access and Effective Assistance
92
Managing Managing Information TechnologyInformation Technology
Managing Managing Information TechnologyInformation Technology
ManagingInformationTechnology
ManagingInformationTechnology
Supplier Customer
Superfast Producers
Cross-FunctionalIntegration
Business Pressures Technology Base
95
Five Leadership Roles
Understand the business
Establish credibility of the systems department
Increase the technological maturity of the firm
Create a vision of the future and sell it
Implement an information system architecture
96
Five waves of innovation
Wave 1: Reducing costWave 1: Reducing cost
Wave 2: Leveraging investmentsWave 2: Leveraging investments
Wave 3: Enhancing products and servicesWave 3: Enhancing products and services
Wave 4: Enhancing executive decision- makingWave 4: Enhancing executive decision- making
Wave 5: Reaching the consumerWave 5: Reaching the consumer
97
Five attitudes toward ITFive attitudes toward IT
The majority of CEOs interviewed -- 52% to be exact -- are neutral, believing they do not have enough knowledge to direct IT investments.
Quadrant 1: High degree of confidence in receiving benefits from IT investments. 12%
Quadrant 2: Aware that implementation problems can destroy that potential. 26%
Quadrant 3: Pessimistic,All systems will be delivered over-budget. 8%
Quadrant 4: IT is harmful because it introduces chaos and too much change for people to cope well. 2%
100
Complete Decentralization
MIS personnel are members of user departments
Marketing
Finance
Accounting
Human Resource Management
101
Hardware CentralizationAdvantages
Easier to share• Data
• Expensive hardware (printers)
Easier to control• Purchases
• Usage
Less duplication
Efficiency — less unused resources
102
Hardware DecentralizationAdvantages
Less chance of total breakdownLess chance of total breakdown
Users get personalized equipmentUsers get personalized equipment
Micros are cheaper than mainframesMicros are cheaper than mainframes
103
Software CentralizationAdvantages
Compatibility
Bulk buying discounts
Easier training
Ease of maintenance & upgrades
104
Software DecentralizationAdvantages
Different users have different preferences
Easier access
Customization without affecting others
Can overcome objections• Lower prices minimize benefits of bulk purchases.• Similarities of packages make training easier.
• Conversion tools enable sharing.
105
Data CentralizationAdvantages
Easy backup
Easier to Share
Less duplication
Security control\monitoring
106
Data DecentralizationAdvantages
Not all data needs to be sharedNot all data needs to be shared
Easier find and accessEasier find and access
Control & politicsControl & politics
107
Personnel CentralizationAdvantages
Workers with similar backgrounds
Easier training
Straightforward growth path
Specialized staff
Easier to see/control costs
108
Personnel DecentralizationAdvantages
Closer to users• Faster response• More time spent with users• Better understanding/communication
Different career path
109
Decentralization Summary
Organizational
Are operations interdependent? -planning -development -physical resources -operations
Can subunits relate solely through information & messages?
Does corporate culture support decentralization?
Strengths
End users gain control.
Supports workgroups.
Enables new organizational structures.
Increased organizational flexibility.
Weaknesses
Possible short term bias in decision making.
Might not be optimal use of resources for corporation.
IS staff might lose cohesiveness and support.
110
Intermediate (Client-Server)
Marketing
Accounting
Finance
Human ResourceManagement
Central MIS staff:Operations, networkand systems programmers
Server Hardware
Shared Data& Software
MIS support
MIS support•Transaction processing•Corporate standards•Network management•Shared databases
111
Client-Server Benefits
Immediate1 to 2 years
Users
Near-Term3 to 5 years
SystemIntegration
Long Term6 to 10 yearsIT Efficiency
Better access todata
Tighter integra-tion across thecompany
Resourceutilization
Increasedparticipation
Faster ITresponses
Newtechnology
Improvedproductivity
Businessprocessreengineering
Adaptivesystems