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Developing Business/IT Solutions
Chapter 10
Copyright © 2010 by the McGraw-Hill Companies, Inc. All rights reserved.McGraw-Hill/Irwin
10-2
Learning Objectives
Use the systems development process outlined in this chapter and the model of IS components from Chapter 1 to help you propose information systems solutions to simple business problems
Describe and give examples to illustrate how you might use each of the steps of the information systems development cycle to develop and implement a business information system
10-3
Learning Objectives
Explain how prototyping can be used as an effective technique to improve the process of systems development for end users and IS specialists
Understand the basics of project management and their importance to a successful system development effort
Identify the activities involved in the implementation of new information systems
10-4
Learning Objectives
Compare and contrast the four basic system conversation strategies
Describe evaluation factors that should be considered in evaluating the acquisition of hardware, software, and IS services
Identify several change management solutions for user resistance to the implementation of new information systems
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IS Development
When the systems approach is applied to the development of an information systems solution to business problems, it is called– Information systems development or – Application development
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The Systems Approach
A problem solving techniquewith a systems orientation
Recognize and define the problem or opportunity
Develop an appropriate, feasible solution
Develop and evaluate alternative solutions
Select the solution that best meets your needs
Design the selected solution
Implement the solution
Evaluate the success of the system
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What is Systems Thinking?
Seeing the forest and the trees in situations– Seeing interrelationships among systems
rather than linear cause-and-effect chains– Seeing processes of change among systems
rather than discrete snapshots of change
See the system in any situation– Find the input, processing, output, feedback
and control components
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Systems Thinking Example
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Systems Analysis and Design
SA&D is the overall process by which information systems are designed and implemented– Identification of business problems
– Propose an IS solution
– Design and implement the proposed solution
Two most common approaches– Object-oriented analysis and design– Life cycle
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Systems Development Lifecycle (SDLC)
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Systems Development Process
Systems Investigation
The first step in the systems development process
May involve consideration of proposals generated by a
business/IT planning process
Also includes the preliminary feasibility study of proposed information system solutions
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Systems Development Process
Feasibility Study: a preliminary study to determine…
Information needs of prospective users
Resource requirements
Costs
Benefits
Feasibility
Sometimes unnecessary
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Operational Feasibility
How well the proposed system will…
Support the business priorities of the organization
Solve the identified problem
Fit with the existingorganizational structure
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Economic Feasibility
Assessment of
Cost savings
Increased revenue
Decreasedinvestment
requirements
Increased profits
Cost/benefitanalysis
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Technical Feasibility
Can the following meet the needs of a proposed system and can be acquired or developed in the required time?– Hardware– Software– Network
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Human Factors Feasibility
Customers
Suppliers
Employees
Management support
Find the right people for the new or revised roles
Assess the acceptance level of…
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Legal/Political Feasibility
Assess
Possible patent or copyright violations
Violations of antitrust laws
Foreign trade restrictions
Any existing contractual obligations
Changes to existing reporting and power structures
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Systems Analysis
An in-depth study of end user information needs– Produces functional requirements used as the
basis for the design of an information system
Typically involves a detailed study – Information needs of a company & end users– Activities, resources, and products of the
information systems currently being used– Information system capabilities required to
meet the information needs of business stakeholders
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Organizational Analysis
Study of the organization, including…
Input / output
Management structure
People
Current information systems
Business activities
Environmental systems
Processing
Storage
Control
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Analysis of the Present System
NetworkNetwork
Hardware and softwareHardware and software
People resources used to convert data resources into information products
People resources used to convert data resources into information products
Before designing a new system, studythe system being improved or replaced
System activities of input, processing,output, storage, and control
System activities of input, processing,output, storage, and control
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Logical Analysis
Allows an analyst to understand the processes, functions, and
data associated with a system, without getting bogged down with hardware and software
Allows an analyst to understand the processes, functions, and
data associated with a system, without getting bogged down with hardware and software
Displays what the current system does, without regard to
how it does it
Displays what the current system does, without regard to
how it does it
A logical model is a blueprint of
the current system
A logical model is a blueprint of
the current system
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Functional Requirements
Determine what type of informationeach business activity requires
Determine the information processing capabilitiesrequired for each system activity
The goal is to identify what should be done,not how to do it
This systems analysis step isone of the most difficult
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Examples of Functional Requirements
Automatic entry of product data andeasy-to-use screens for Web customers
User Interface
Fast, automatic calculation ofsales totals and shipping costs
Processing
Fast retrieval and update of data fromproduct, pricing, and customer databases
Storage
Signals for data entry errors and quicke-mail confirmation to customers
Control
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Three Areas of Systems Design Focus
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Prototyping
Prototyping is the rapid development and testing of working models– An interactive, iterative process used during
the design phase– Makes development faster and easier,
especially when end user requirements are hard to define
– Enlarged the role of business stakeholders
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Prototyping Life Cycle
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User Interface Design
Focuses on supporting the interactions betweenend-users and their computer-based applications
Produces detailed design
specifications for information
products, such as display screens
Designers concentrate
on the design of attractive and efficient forms of user
input and output
Frequently a prototyping
process
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Checklist for Corporate Websites
IncompatibilitiesIncompatibilities
Easy to navigateEasy to navigate
Remember the customer
Remember the customer
Registrationforms
Registrationforms
AestheticsAesthetics
Dead linksDead links
SearchabilitySearchability
Broadbandcontent
Broadbandcontent
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System Specifications
ProcessingproceduresProcessingprocedures
Controlprocedures
Controlprocedures
DatabasestructuresDatabasestructures
User interfacemethods and
products
User interfacemethods and
products
Formalizingthe design of
Formalizingthe design of
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Examples of System Specifications
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End-User System Development
IS professionals play a consulting role, while users do their own application development– Consultants may be available to help with
analysis, design, and installation
Other support– Application package training– Hardware and software advice– Help gaining access to organization databases
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Focus on IS Activities
End-user documentation should focus on the fundamental activities of an information system
Input
Processing
Output
Storage
Control
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Focus of End-User Development
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End-User Application Development
Application development capabilities are often built into software packages– Makes it easier for users to develop their
own solutions
To encourage end-user Web development– Look for tools that make sense– Spur creativity– Set some limits– Give managers responsibility– Make users comfortable
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Object-Oriented Analysis and Design
Object-oriented programming (OOP)– Uses objects to design applications
– Employs inheritance, modularity, polymorphism, encapsulation
Popular OOP programming languages– C++, Delphi, Java, JavaScript, Perl, PHP,
RealBasic, Ruby, VB.Net, Visual FoxPro
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Object-Oriented Analysis and Design
Object-oriented analysis (OOA)
– Aims to model the problem domain by developing an object-oriented system
– Does not take into account implementation constraints, nor how the system will be built
– Produces a description of what is to be built, using concepts and relationships between concepts
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Object-Oriented Analysis and Design
Object-oriented design (OOD)– Designers look for logical solutions to solve
a problem using objects
– Takes the conceptual model from OOA and adds implementation constraints
Concepts in the conceptual model are mapped to– Concrete classes and abstract interfaces
– Roles that objects take in various situations
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Implementing New Systems
The systems implementation stage involves
Hardware and software acquisition
Software development
Testing of programs and procedures
Conversion of data resources
Conversion alternatives
Education/training of end-users and specialistswho will operate the new system
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Implementation Process
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Sample Implementation Process
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Project Management
The skills and knowledge necessary to be a good project manager will translate into virtually any project environment– The people who have acquired them
are sought after by most organizations
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What is a Project?
Every project has– A set of activities with a clear beginning
and end– Goals and objectives– Tasks– Limitations or constraints– A series of steps or phases
Managing a project effectively requires– Process– Tools– Techniques
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Phases of Project Management
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Evaluating Hardware, Software, Services
Establish minimum physical and performance characteristics for all hardware and software– Formalized in an RFP/RFQ
Send RFQ to appropriate vendors
Evaluate bids when received– All claims must be demonstrated– Obtain recommendations from other users– Search independent sources for evaluations– Benchmark test programs and test data
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Hardware Evaluation Factors
PerformancePerformance
ScalabilityScalability
ErgonomicsErgonomics
ReliabilityReliability
SoftwareSoftware
CostCost
CompatibilityCompatibility
SupportSupport
ConnectivityConnectivity
TechnologyTechnology
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Software Evaluation Factors
Hardware evaluation factors apply to software,
as do these…
Quality
Efficiency
Flexibility
Security
Connectivity
Maintenance
Documentation
Hardware
Software that is slow, hard to use, bug-filled, or poorly
documented is not a good choice at any price
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Evaluating IS Services
Examples of IS Services
Developing a company website
Installation or conversion of hardware/software
Employee training
Hardware maintenance
System design and/or integration
Contract programming
Consulting services
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IS Service Evaluation Factors
PerformancePerformance
Business position & financial strength
Business position & financial strength
Backup facilities and services
Backup facilities and services
MaintenanceMaintenance
Hardware selection and compatibility
Hardware selection and compatibility
Systems development
Systems development
ConversionConversion
Software packages offered
Software packages offered
Accessibility to sales & support
Accessibility to sales & support
TrainingTraining
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Other Implementation Activities
The keys to successful implementation of a new business system– Testing– Data conversion– Documentation– Training
System testing involves– Testing and debugging software– Testing website performance– Testing new hardware– Review of prototypes
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Data Conversion
Correcting data errors
Filtering out unwanted data
Data conversion to new database
Consolidating data from multiple databases
Organizing data into new data subsets
Improperly organized and formatted datais a major cause of implementation failures
There is no standard format for a job description,but most include…
10-51
Documentation
User Documentation– Sample data entry screens, forms, reports– System operating instructions
Systems Documentation– Method of communication among those
developing, implementing, and maintaining a computer-based system
– Detailed record of the system design– Extremely important when diagnosing
problems and making system changes
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Training
End users must be trained to operate a newbusiness system or its implementation will fail
End users must be trained to operate a newbusiness system or its implementation will fail
May involve only activities, such as data entry, or all aspects of system use
May involve only activities, such as data entry, or all aspects of system use
Managers and end-users must both understand
how the new technology
impacts business
operations
Managers and end-users must both understand
how the new technology
impacts business
operations
System training should be
supplemented with hardware
device and software training
System training should be
supplemented with hardware
device and software training
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Major System Conversion Strategies
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Direct Conversion
Simplest conversion strategy
Most disruptive to the organization
Sometimes called slam dunk or cold turkey
Highest risk of failure
Turns off old system, turns on new one
May be only solution in emergency implementations, or if old and new system can’t coexist
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Parallel Conversion
Old and new systems run simultaneously until everyone is satisfied that– The new system functions correctly, and
the old system is no longer needed
Conversion cutover can be single or phased
Lowest risk, but highest cost– Up to 4 times more than using old system
Best choice where an automated system is replacing a manual one
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Pilot Conversion
Scenarios best suited to a pilot conversion– Multiple business locations– Geographically diverse locations
Advantages of single location conversion– Can select a location that best represents
the conditions across the organization– Less risky in terms of loss of time or delays
in processing– Can be evaluated and changed before
further installations
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Phased Conversion
Phased or gradual
conversion
Takes advantage of both thedirect and parallel approaches
Minimizes the risks involved
Allows new system to come online as logically ordered functional components
DisadvantagesTakes the most time
Most disruptive to theorganization over time
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Post-Implementation Activities
The single most costly activity
Correcting errors or faults in the system
Improving system performance
Adapting the system to changes in theoperating or business environment
Requires more programmers thanfor application development
May exist for years
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Systems Maintenance Categories
Corrective Adaptive
Preventive
Perfective
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Post-Implementation Review
Ensures that the newly implemented system meets the established business objectives– Errors must be corrected by the maintenance
process– Includes a periodic review/audit of the
system, as well as continuous monitoring
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Implementation Challenges
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User Resistance and Involvement
Solving User Resistance Problems
Education and training
User involvement in organizational changes, IS development
End-user participation before new system is implemented
Involvement, commitment of top managementand all business stakeholders
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Key Dimensions of Change Management
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Change Management
People are a major focus of change management
– Involve as many people as possible in e-business planning and application development
– Make constant change an expected part of the culture
– Tell everyone as much as possible about everything, as often as possible, in person
– Make liberal use of financial incentives and recognition
– Work within the company culture, not around it
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Change Management Process
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Implementation Process
New systemimplementation
process
Acquisition Conversion
Softwaredevelopment Documentation
Dataconversion Testing
Training