Systems Development
Chapter 8
Fundamentals of Information
Systems, Second Edition
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Top Uses for New Systems in Various
Industries
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Participants in System Development
• Stakeholders: Those that benefit from the project
• Users: Those that will interact with and use the
system
• Project Manager: Person responsible for
coordinating all resources in the project
– Human resources (who should participate in the
project, what she should do, etc.)
– Equipment (what is needed to carry out the project,
servers, hubs, etc.)
– Travel (does the project require traveling to other
places, if so, when, or how often)
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Participants in System Development
• Systems Analyst: Analyzes and designs
business systems
– Sees the system as a whole
– Design the whole system so that it fulfils the
requirements
– Detect potential problems early on
• Programmer: Develop the system based on user
requirements
• Technical Specialists: Hardware engineers, DB
engineers, etc.
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Participants in Systems Development
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Information Systems Planning
• Decide on
organizational goals
• Discuss how these can
be achieved with IS
• Plan on IS
development
• Develop individual
components
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Systems Development Life
Cycles and Approaches
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The Traditional SDLC
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The Traditional SDLC
• Systems investigation
– Identify problems and opportunities
– Worth solving it; what are the benefits?
• Systems analysis
– What will it take to solve this problem?
– Study existing systems
– Generate list of requirements
• Systems Design
– What must be done to achieve the solution?
– Generate technical design (either new system or an
improved system)
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The Traditional SDLC
• Systems implementation
–
–
–
–
Create individual components
Combine them to have a working system
Train users so that they can use the system easily
Install the system
• Systems maintenance and review
– Make sure that the system operates as expected
– Modify functionalities that are not working properly
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Prototyping is an Iterative Approach to
Systems Development
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Rapid Application Development (RAD)
• Employs tools, techniques, and methodologies
designed to speed application development
• Reduces paper-based documentation
• Automatically generates program code
• Extreme Programming (EP): Change code as
you go along
• Joint Application Development (JAD) – Used
for data collection and requirements analysis.
• JAD: Participants come together and discuss
requirements, needs, etc.
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Advantages and Disadvantages of RAD
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Use of Project Management Tools
• Aim: Plan, schedule, direct resources
• Project schedule:
– Details description of what will be done
– What are smaller parts (activities)?
– How long will each activity will take?
• Project milestone
– Critical date for the completion of a part of the project
– Ex: First release
• Project deadline
– The date for the entire project to be ready
– The date is based on client’s needs
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Use of Project Management Tools
• Critical path
– All activities that will cause a delay if they are delayed
– Such activities must be finished on time
• Program Evaluation and Review Technique
(PERT)
– Three time estimates: Shortest possible, most likely,
and the upper bound
• Gantt chart: Graphical tool for planning and
monitoring activities
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Gantt Chart
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Selected Project Management Software
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Computer-Aided Software Engineering
(CASE) Tools
• Automate many of the tasks required in a
systems development effort
– Rigorous
– Standard systems development process
• Upper-CASE tools
– Deal with early stages of development
• Lower-CASE tools
– Automatically generate structured program code
• Integrated-CASE tools
– Provide links between upper- and lower-CASE
packages.
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Object-Oriented Systems Development
• Identify potential problems and opportunities within the organization
that would be appropriate for the OO approach
• Define the kind of system users require
• Design the system
• Program or modify modules
• Evaluation by users
• Periodic review and modification
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Use Case Diagram for a Kayak Rental
Application
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Systems Development Maturity Based on the
Capability Maturity Model (CMM)
• Initial: No discipline; ad
hoc
• Repeatable: Track costs,
schedules, functionality
• Defined: Use documented
and defined procedures
• Managed: Use measures;
monitor and improve
system development
• Optimized: Improve
continuously
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Systems Investigation
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Systems Investigation
• Attempts to answer the following questions:
– What primary problems might a new or enhanced
system solve?
– What opportunities might a new or enhanced system
provide?
– What new hardware, software, databases, or
procedures will improve an existing system?
– What are the potential costs (variable and fixed)?
– What are the associated risks?
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Feasibility Analysis
• T: Whether hardware, software, and
other components can be developed
to solve the problem
• E: Are the predicted benefits more
than the cost?
• L: Do laws and regulations permit its
usage?
• O: Can it be put into action?
• S: Can it be finished in a reasonable
time?
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Systems Investigation Report
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Systems Analysis
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Systems Analysis
• Data Collection
– Seeks additional information about the problems
– Requires identification of internal and external
sources
• Data Analysis
– Manipulates collected data so that it is usable for the
development team
– Uses data and activity modeling
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Internal and External Sources of Data
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The Steps in Data Collection
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Modeling
• Data Modeling
– Mostly done by entity-relationship diagrams
– Describes the objects and their relationships but not
the activities
• Activity Modeling
– Done by data-flow diagrams (DFMs)
– Models objects, activities
– Describe how data flows between objects
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Data and Activity Modeling
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Requirements Analysis
• Asking directly
– To stakeholders, users, etc. their needs
– Critically evaluate needs
– Keep in mind that some needs are contradictory
• Determining critical success factors (CSFs)
– Managers and decision makers list critical factors only
– Derive other requirements based on this
• Developing the IS plan
– Translate strategic and organizational goals into
systems development
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The Systems Analysis Report
• The report should cover the following:
– The strengths and weaknesses of the existing system
from a stakeholder’s perspective
– The user/stakeholder requirements for the new
system (also called the functional requirements)
– The organizational requirements for the new system
– A description of what the new information system
should do to solve the problem
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Converting Organizational Goals into
Systems Requirements
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A Typical Table of Contents for a
Report on an Existing System
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Systems Design
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Systems Design
• Logical design
– What will the system do to solve the problems
identified earlier?
– Plan the purpose of each system element
– Ex: Output of the system, the needed inputs
• Physical design
– Refers to how the tasks are accomplished
– How do the components work together
– What does each component do?
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Request for Proposal
One of the most important documents generated
during systems development.
• Results in a formal bid that is used to determine
who gets a contract for new or modified
systems.
• Specifies in detail required resources.
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A Typical Table of Contents for a
Request for Proposal
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Advantages and Disadvantages of Acquisition Options
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Freezing Design Specifications
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A Typical Table of Contents for a Systems
Design Report
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Systems Implementation
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Typical Steps in Systems Implementation
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Typical Steps in Systems Implementation
• Hardware: Buy new or used or refurbished
• Software:
– Make-or-buy decision
– Reuse existing software
• Users: Train them to use the software fast and
with ease
• Personnel: Similar but more technical training for
the personnel
• Site preparation: Find a place for the system,
ensure environmental constraints
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Typical Steps in Systems Implementation
• Data preparation: Convert physical files into
computer data
• Installation: Physically place the system on the
site and make it operational
• Testing: Make sure the system operates as
planned
–
–
–
–
–
Unit: Each component
System: System as a whole
Volume: Test the system with lots of data
Integration: Test all related systems
Acceptance: Test user cases
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Types of Testing
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Start-up Approaches
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Systems Maintenance and
Review
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Systems Maintenance
• Reasons for program maintenance include:
– Changes in business processes
– New requests from stakeholders, users, and
managers
– Bugs or errors in the program
– Technical and hardware problems
– Corporate mergers and acquisitions
– Government regulations
– Change in the operating system or hardware on
which the application runs
– Unexpected events, like the terrorist attacks of
September
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Examples of Review Types
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Summary
• Systems development team - consists of stakeholders,
users, managers, systems development specialists, and
various support personnel.
• Five phases of the traditional SDLC - investigation,
analysis, design, implementation, and maintenance and
review.
• Systems investigation - designed to assess the
feasibility of implementing solutions for business
problems.
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Summary
• Systems analysis - the examination of existing systems, which
begins once approval for further study is received from
management.
• Systems design – purpose is to prepare the detailed design needs
for a new system or make modifications to an existing one.
• Systems implementation - to install a system and make
everything, including users, ready for its operation.
• Systems maintenance - involves checking, changing, and
enhancing the system to make it more useful in obtaining user and
organizational goals.
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Principles and Learning Objectives
• Effective systems development requires a
team effort of stakeholders, users, managers,
systems development specialists, and various
support personnel, and it starts with careful
planning.
– Identify the key participants in the systems
development process and discuss their roles.
– Define the term information systems planning and
list several reasons for initiating a systems project.
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Principles and Learning Objectives
• Systems development often uses different approaches
and tools such as traditional development, prototyping,
rapid application development, end-user development,
computer-aided software engineering, and objectoriented development to select, implement, and monitor
projects.
– Discuss the key features, advantages, and disadvantages of the
traditional, prototyping, rapid application development, and enduser systems development life cycles.
– Discuss the use of computer-aided software engineering (CASE)
tools and the object-oriented approach to systems development.
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Principles and Learning Objectives
• Systems development starts with investigation
and analysis of existing systems.
– State the purpose of systems investigation.
– Discuss the importance of performance and cost
objectives.
– State the purpose of systems analysis and discuss
some of the tools and techniques used in this phase
of systems development.
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Principles and Learning Objectives
• Designing new systems or modifying existing
ones should always be aimed at helping an
organization achieve its goals.
– State the purpose of systems design and discuss the
differences between logical and physical systems
design.
– Outline key steps taken during the design phase.
– Define the term RFP and discuss how this document
is used to drive the acquisition of hardware and
software.
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Principles and Learning Objectives
• The primary emphasis of systems
implementation is to make sure that the right
information is delivered to the right person in the
right format at the right time.
– State the purpose of systems implementation and
discuss the various activities associated with this
phase of systems development.
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Principles and Learning Objectives
• Maintenance and review add to the useful life of
a system but can consume large amounts of
resources, so they benefit from the same
rigorous methods and project management
techniques applied to systems development.
– State the importance of systems and software
maintenance and discuss the activities involved.
– Describe the systems review process.
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