Systems Analysis & Design
Sixth Edition
Chapter 9
Phase Description
● Systems Implementation is the fourth of
five phases in the systems development
life cycle (SDLC)
● Includes application development,
testing, documentation, training, data
conversion, system changeover, and
post-implementation evaluation of the
results
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Chapter Objectives
● Explain the importance of software quality
assurance and software engineering
● Describe the application development process
● Draw a structure chart showing top-down
design, modular design, cohesion, and coupling
● Explain the coding process and how code is
generated
● Explain unit testing, integration testing, and
system testing
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Chapter Objectives
● Differentiate between program, system,
operations, and user documentation
● List the main steps in system installation
and evaluation
● Develop an overall training plan with
specific objectives for each group of
participants, compare in-house and
outside training providers, and describe
effective training techniques
4
Chapter Objectives
● Describe the data conversion process
● Identify and describe changeover
methods
● Explain post-implementation evaluation
● Describe the final report to management
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Introduction
● The system design specification serves as a
blueprint for constructing the new system
● The initial task is application development
● Before a changeover can occur, the system
must be tested and documented carefully,
users must be trained, and existing data must
be converted
● A formal evaluation of the results takes place
as part of a final report to management
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Software Quality Assurance
● Quality assurance
● Software Engineering
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Software Engineering Institute (SEI)
Capability Maturity Model (CMM)
Capability Maturity Model Integration (CMMI)
Process improvement
CMMI tracks an organization's processes, using
five maturity layers
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Software Quality Assurance
● International Organization for
Standardization (ISO)
– Many firms seek assurance that software
systems will meet rigid quality standards
– In 1991, ISO established a set of guidelines
called ISO 9000-3
– ISO requires a specific development plan,
which outlines a step-by-step process for
transforming user requirements into a finished
product
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Overview of Application Development
● Application development
● Objective is to translate the logical
design into program and code modules
that will function properly
● Creation of the System Design
– The tasks involved in system design produced
an overall design and a plan for physical
implementation
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Overview of Application Development
● Application
Development Steps
– Module
– Start by reviewing
documentation from
prior SDLC phases and
creating a set of
program designs
– After the design is
created, coding can
begin
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Overview of Application Development
● Project Management
– Even a modest-sized project might have
hundreds or even thousands of modules
– Important to set realistic schedules, meet project
deadlines, control costs, and maintain quality
– Should use project management tools and
techniques
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Structured Application Development
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Top-down approach
Partitioning
Modular design
Must proceed carefully, with constant
input from programmers and IT
management to achieve a sound, wellintegrated structure
● Must ensure that integration capability
is built into each design and thoroughly
tested
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Structured Application Development
● Structure Charts
– Structure charts show the program modules and
the relationships among them
– Control module
– Subordinate modules
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Structured Application Development
● Structure Charts
– Module
• Library module
– Data Couple
– Control Couple
• Flag
• A module uses a flag to signal a specific condition or
action to another module
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Structured Application Development
● Structure Charts
– Condition
• A condition line indicates that a control module
determines which subordinate modules will be
invoked, depending on a specific condition
– Loop
• A loop indicates that one or more modules are
repeated
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Structured Application Development
● Cohesion and Coupling
– If you need to make a module more cohesive,
you can split it into separate units, each of
which performs a single function
– Loosely coupled
– Tightly coupled
– Status flag
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Structured Application Development
● Structure Chart Examples
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Structured Application Development
● Drawing a Structure Chart
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Step 1: Review the DFDs
Step 2: Identify Modules and Relationships
Step 3: Add Couples, Loops, and Conditions
Step 4: Analyze the Structure Chart and the
Data Dictionary
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Structured Application Development
● Other Structured Development Tools
– Program Flowcharts
– Pseudocode
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Object-Oriented Application
Development
● Object-Oriented Application
Development Compared to Structured
Development
– When implementing an object-oriented design,
relationships between objects already exist
– The application's structure is represented by the
object model itself
– Attributes
– Methods
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Object-Oriented Application
Development
● Implementation of Object-Oriented
Design
– Programmer makes necessary revisions and
updates to class diagrams, sequence diagrams,
state transition diagrams, and activity diagrams
– Main objective is to translate object methods into
program code modules and determine what
event or message will trigger the execution of
each module
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Coding
● Coding
● Programming Environments
– Each IT department has its own programming
environment and standards
– Integrated development environments (IDEs)
● Generating Code
– Can generate editable program code directly
from macros, keystrokes, or mouse actions
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Testing the System
● After coding, a programmer must test
each program to make sure that it
functions correctly
● Syntax errors
● Desk checking
– Logic errors
● Structured walkthrough, or code review
● Design walkthrough
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Testing the System
● Unit Testing
– Test data
– Programmers must test programs that
interact with other programs and files
individually
– Stub testing
– Regardless of who creates the test plan, the
project manager or a designated analyst also
reviews the final test results
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Testing the System
● Integration Testing
– Integration testing, or link testing
– Testing the programs independently does not
guarantee that the data passed between them is
correct
– A testing sequence should not move to the
integration stage unless it has performed
properly in all unit tests
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Testing the System
● System Testing
– Major objectives:
• Perform a final test of all programs
• Verify that the system will handle all input data
properly, both valid and invalid
• Ensure that the IT staff has the documentation
and instructions needed to operate the system
properly and that backup and restart capabilities
of the system are adequate
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Testing the System
● System Testing
– Major objectives:
• Demonstrate that users can interact with the system
successfully
• Verify that all system components are integrated
properly and that actual processing situations will be
handled correctly
• Confirm that the information system can handle
predicted volumes of data in a timely and efficient
manner
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Testing the System
● System Testing
– Acceptance tests
– You should regard thorough testing as a costeffective means of providing a quality product
– If conflicting views exist, management will
decide whether or not to install the system after
a full discussion of the options
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Documentation
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Documentation
Program Documentation
System Documentation
Operations Documentation
User Documentation
– Online documentation
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Management Approval
● After system testing is complete, you
present the results to management
● If system testing produced no technical,
economical, or operational problems,
management determines a schedule for
system installation and evaluation
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System Installation and Evaluation
● Remaining steps in systems
implementation:
– Prepare a separate operational and test
environment
– Provide training for users, managers, and IT
staff
– Perform data conversion and system
changeover
– Carry out post-implementation evaluation of
the system
– Present a final report to management
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Operational and Test Environments
● The environment for the actual system
operation is called the operational
environment or production environment
● The environment that analysts and
programmers use to develop and
maintain programs is called the test
environment
● A separate test environment is necessary
to maintain system security and integrity
and protect the operational environment
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Operational and Test Environments
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Training
● Training Plan
– The first step is to identify who should receive
training and what training is needed
– The three main groups for training are users,
managers, and IT staff
– You must determine how the company will
provide training
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Training
● Vendor Training
– If the system includes the purchase of
software or hardware, then vendor-supplied
training is one of the features you should
include in the RFPs (requests for proposal)
and RFQs (requests for quotation) that you
send to potential vendors
– Often gives the best return on your training
dollars
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Training
● Outside Training Resources
– Many training consultants, institutes, and firms
are available that provide either standardized or
customized training packages
– You can contact a training provider and obtain
references from clients
– Center for the Application of Information
Technologies (CAIT)
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Training
● In-House Training
– The IT staff and user departments often share
responsibility
– When developing a training program, you
should keep the following guidelines in mind:
• Train people in groups, with separate training
programs for distinct groups
• Select the most effective place to conduct the training
• Provide for learning by hearing, seeing, and doing
• Prepare effective training materials, including
interactive tutorials
• Tutorial
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Training
● In-House Training
– When developing a training program, you should
keep the following guidelines in mind:
• Rely on previous trainees
• Train-the-trainer strategy
– When Training is complete, many organizations
conduct a full-scale test, or simulation
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Data Conversion
● Data Conversion Strategies
– The old system might be capable of exporting
data in an acceptable format for the new
system or in a standard format such as ASCII or
ODBC
– If a standard format is not available, you must
develop a program to extract the data and
convert it
– Often requires additional data items, which
might require manual entry
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Data Conversion
● Data Conversion Security and Controls
– You must ensure that all system control
measures are in place and operational to protect
data from unauthorized access and to help
prevent erroneous input
– Some errors will occur
– It is essential that the new system be loaded
with accurate, error-free data
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System Changeover
● Direct Cutover
– Involves more risk than other changeover
methods
– Companies often choose the direct cutover
method for implementing commercial software
packages
– Cyclical information systems usually are
converted using the direct cutover method at
the beginning of a quarter, calendar year, or
fiscal year
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System Changeover
● Parallel Operation
– Easier to verify that the new system is working
properly under parallel operation than under
direct cutover
– Running both systems might place a burden
on the operating environment and cause
processing delay
– Is not practical if the old and new systems are
incompatible technically
– Also is inappropriate when the two systems
perform different functions
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System Changeover
● Pilot Operation
– The group that uses the new system first is
called the pilot site
– The old system continues to operate for the
entire organization
– After the system proves successful at the pilot
site, it is implemented in the rest of the
organization, usually using the direct cutover
method
– Is a combination of parallel operation and
direct cutover methods
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System Changeover
● Phased Operation
– You give a part of the system to all users
– The risk of errors or failures is limited to the
implemented module only
– Is less expensive than full parallel operation
– Is not possible, however, if the system cannot
be separated easily into logical modules or
segments
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Post-Implementation Tasks
● Post-Implementation Evaluation
– Includes feedback for the following areas:
• Accuracy, completeness, and timeliness of information
system output
• User satisfaction
• System reliability and maintainability
• Adequacy of system controls and security measures
• Hardware efficiency and platform performance
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Post-Implementation Tasks
● Post-Implementation Evaluation
– Includes feedback for the following areas:
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Effectiveness of database implementation
Performance of the IT team
Completeness and quality of documentation
Quality and effectiveness of training
Accuracy of cost-benefit estimates and development
schedules
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Post-Implementation Tasks
● Post-Implementation Evaluation
– When evaluating a system, you should:
• Interview members of management and key users
• Observe users and computer operations personnel
actually working with the new information system
• Read all documentation and training materials
• Examine all source documents, output reports, and
screen displays
• Use questionnaires to gather information and opinions
form a large number of users
• Analyze maintenance and help desk logs
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Post-Implementation Tasks
● Post-Implementation Evaluation
– Users can forget details of the developmental
effort if too much time elapses
– Pressure to finish the project sooner usually
results in an earlier evaluation in order to
allow the IT department to move on to other
tasks
– Ideally, conducting a post-implementation
evaluation should be standard practice for all
information systems projects
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Post-Implementation Tasks
● Final Report to Management
– Your report should include the following:
• Final versions of all system documentation
• Planned modifications and enhancements to the
system that have been identified
• Recap of all systems development costs and
schedules
• A comparison of actual costs and schedules to the
original estimates
• Post-implementation evaluation, if it has been
performed
– Marks the end of systems development work
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Chapter Summary
● Develop a training program
● Data conversion often is necessary
when installing a new information
system
● System changeover is the process of
putting the new system into operation
● A post-implementation evaluation
assesses and reports on the quality of
the new system and the work done by
the project team
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Chapter Summary
● The final report to management includes
the final system documentation,
describes any future system
enhancements that already have been
identified, and details the project costs
● Chapter 9 complete
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