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Fundamentals of Information Systems
Fourth Edition
Chapter 8
Systems Development
Fundamentals of Information Systems, Fourth Edition 2
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
discuss the importance of planning a project
Fundamentals of Information Systems, Fourth Edition 3
Principles and Learning Objectives (continued)
• Systems development often uses different approaches and tools such as traditional development, prototyping, rapid application development, end-user development, computer-aided software engineering, and object-oriented development to select, implement, and monitor projects– Discuss the key features, advantages, and
disadvantages of the traditional, prototyping, rapid application development, and end-user systems development life cycles
Fundamentals of Information Systems, Fourth Edition 4
Principles and Learning Objectives (continued)
• Systems development often uses different approaches and tools such as traditional development, prototyping, rapid application development, end-user development, computer-aided software engineering, and object-oriented development to select, implement, and monitor projects (continued)– Discuss the use of computer-aided software
engineering (CASE) tools and the object-oriented approach to systems development
Fundamentals of Information Systems, Fourth Edition 5
Principles and Learning Objectives (continued)
• Systems development starts with investigation and analysis of existing systems– State the purpose of systems investigation– State the purpose of systems analysis and discuss
some of the tools and techniques used in this phase of systems development
Fundamentals of Information Systems, Fourth Edition 6
Principles and Learning Objectives (continued)
• 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
– Define the term RFP and discuss how this document is used to drive the acquisition of hardware and software
Fundamentals of Information Systems, Fourth Edition 7
Principles and Learning Objectives (continued)
• 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
Fundamentals of Information Systems, Fourth Edition 8
Principles and Learning Objectives (continued)
• 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
Fundamentals of Information Systems, Fourth Edition 9
Why Learn About Systems Development?
• Important to learn how to:– Initiate systems development process– Analyze your needs with help of IS personnel
• Learn how a project can be:– Planned– Aligned with corporate goals– Rapidly developed
Fundamentals of Information Systems, Fourth Edition 10
An Overview of Systems Development
• Managers and employees in all functional areas work together in a business information system
• Users help and often lead the way with development process
• Participants in systems development: – Determine when a project fails– Are critical to systems development success
Fundamentals of Information Systems, Fourth Edition 11
Participants in Systems Development
• Development team consists of the following:– Project managers: coordinate system development
effort– Stakeholders: directly or indirectly benefit from the
project– Users: interact with the system regularly– Systems analysts: analyze and design business
systems– Programmers: modify or develop programs to satisfy
user requirements– Various support personnel: specialists, vendors
Fundamentals of Information Systems, Fourth Edition 12
Information Systems Planning and Aligning Corporate and IS Goals
• Information systems planning: translating strategic and organizational goals into systems development initiatives
• Aligning organizational goals and IS goals is critical for any successful systems development effort
• Determining whether organizational and IS goals are aligned can be difficult
Fundamentals of Information Systems, Fourth Edition 13
Information Systems Planning and Aligning Corporate and IS Goals
(continued)
Figure 8.2: Information Systems Planning
Fundamentals of Information Systems, Fourth Edition 14
Systems Development Life Cycles
• The systems development process is also called a systems development life cycle (SDLC)
• Common SDLCs– Traditional systems development life cycle – Prototyping– Rapid application development (RAD)– End-user development
Fundamentals of Information Systems, Fourth Edition 15
The Traditional Systems Development Life Cycle
Figure 8.3: The Traditional Systems Development Life Cycle
Fundamentals of Information Systems, Fourth Edition 16
The Traditional Systems Development Life Cycle (continued)
• Systems investigation: problems and opportunities are identified and considered in light of the goals of the business
• Systems analysis: study of existing systems and work processes to identify strengths, weaknesses, and opportunities for improvement
• Systems design: answers the question “How will the information system do what it must do to obtain the problem solution?”
Fundamentals of Information Systems, Fourth Edition 17
The Traditional Systems Development Life Cycle (continued)
• Systems implementation: creation or acquisition of various system components detailed in the systems design, assembling them, and placing the new or modified system into operation
• Systems maintenance and review: ensures the system operates as intended and modifies the system so that it continues to meet changing business needs
Fundamentals of Information Systems, Fourth Edition 18
Prototyping
• An iterative approach to systems development
Figure 8.4: Prototyping
Fundamentals of Information Systems, Fourth Edition 19
Rapid Application Development, Agile Development, Joint Application
Development, and Other Systems Development Approaches
• Rapid application development (RAD)– Systems development approach that employs tools,
techniques, and methodologies designed to speed application development
• Some iterative development approaches allow the system to change as it is being developed– Agile development: frequent face-to-face meetings
between systems developers and users– XP programming: pairs of programmers work
together to develop robust systems quickly
Fundamentals of Information Systems, Fourth Edition 20
Rapid Application Development, Agile Development, Joint Application
Development, and Other Systems Development Approaches (continued)
• Joint application development (JAD)– Process for data collection and requirements
analysis in which users, stakeholders, and IS professionals work together to analyze existing systems, propose possible solutions, and define the requirements of a new or modified system
– Used extensively by RAD– Often utilizes group support systems (GSS) software
to foster positive group interactions
Fundamentals of Information Systems, Fourth Edition 21
The End-User Systems Development Life Cycle
• End-user systems development: any systems development project in which the primary effort is undertaken by a combination of business managers and users
• End-user-developed systems can be structured as complementary to, rather than in conflict with, existing and emerging information systems
Fundamentals of Information Systems, Fourth Edition 22
Outsourcing and On Demand Computing
• An outside consulting firm or computer company that specializes in systems development can take over some or all of the development and operations activities
• Reasons for using outsourcing and on demand computing– Reducing costs, obtaining state-of-the-art
technology, eliminating staffing and personnel problems, and increasing technological flexibility
Fundamentals of Information Systems, Fourth Edition 23
Use of Computer-Aided Software Engineering (CASE) Tools
• Computer-aided software engineering (CASE): tools that automate many of the tasks required in a systems development effort and encourage adherence to the SDLC– Instill a high degree of rigor and standardization to
the entire systems development process– Upper-CASE tools focus on investigation, analysis,
and design– Lower-CASE tools focus on implementation
Fundamentals of Information Systems, Fourth Edition 24
Use of Computer-Aided Software Engineering (CASE) Tools (continued)
Table 8.2: Advantages and Disadvantages of CASE Tools
Fundamentals of Information Systems, Fourth Edition 25
Object-Oriented Systems Development
• Object-oriented systems development (OOSD): approach to systems development that combines the logic of the systems development life cycle with the power of object-oriented modeling and programming
Fundamentals of Information Systems, Fourth Edition 26
Object-Oriented Systems Development (continued)
• Object-oriented systems development typically involves:– Identifying potential problems and opportunities
within the organization that would be appropriate for the OO approach
– Defining the kind of system users require– Designing the system– Programming or modifying modules– Evaluation by users– Periodic review and modification
Fundamentals of Information Systems, Fourth Edition 27
Systems Investigation
• What primary problems might a new or enhanced system solve?
• What opportunities might a new or enhanced system provide?
• What new hardware, software, databases, telecommunications, personnel, or procedures will improve an existing system or are required in a new system?
• What are the potential costs (variable and fixed)?
• What are the associated risks?
Fundamentals of Information Systems, Fourth Edition 28
Initiating Systems Investigation
• Systems request form: document filled out by someone who wants the IS department to initiate systems investigation– Helps rationalize and prioritize the activities of the IS
department– Includes the following information:
• Problems in and opportunities for system
• Objectives in investigation
• Overview, costs, and benefits of proposed system
Fundamentals of Information Systems, Fourth Edition 29
Feasibility Analysis
• Technical feasibility: hardware, software, and other system components
• Economic feasibility: predicted benefits vs. cost and time
• Legal feasibility: limitations of laws and regulations on project
• Operational feasibility: logistical and motivational considerations
• Schedule feasibility: completion of project in reasonable amount of time
Fundamentals of Information Systems, Fourth Edition 30
Object-Oriented Systems Investigation
• Key objects can be identified during systems investigation
• Use case diagram– Part of the Unified Modeling Language (UML) used
in object-oriented systems development– Actors represent objects – Use cases represent events
Fundamentals of Information Systems, Fourth Edition 31
Object-Oriented Systems Investigation (continued)
Figure 8.8: Use Case Diagram for a Kayak Rental Application
Fundamentals of Information Systems, Fourth Edition 32
The Systems Investigation Report
• Systems investigation report – Summary of the results of the systems investigation
and the process of feasibility analysis – Recommendation of a course of action
• Continue systems analysis
• Modify the project
• Abandon the project
– Reviewed by steering committee of senior management and users
Fundamentals of Information Systems, Fourth Edition 33
The Systems Investigation Report (continued)
Figure 8.9: A Typical Table of Contents for a Systems Investigation Report
Fundamentals of Information Systems, Fourth Edition 34
Systems Analysis
• Answers the question “What must the information system do to solve the problem?”
• Overall emphasis of systems analysis is:– Gathering data on the existing system– Determining the requirements for the new system– Considering alternatives within these constraints– Investigating the feasibility of the solutions
• Primary outcome: prioritized list of systems requirements
Fundamentals of Information Systems, Fourth Edition 35
Data Collection
• Identifying sources of data– Internal sources– External sources
• Collecting data– Interviews: structured and unstructured– Direct observation– Questionnaires: structured or unstructured
• Used when data sources are spread over a wide geographic area
Fundamentals of Information Systems, Fourth Edition 36
Data Collection (continued)
Figure 8.10: Internal and External Sources of Data for Systems Analysis
Fundamentals of Information Systems, Fourth Edition 37
Data Analysis
• Data analysis– Manipulation of collected data so that systems
development team can use the data
• Data modeling– Entity-relationship (ER) diagrams: objects, attributes,
and associations
• Activity modeling– Data-flow diagrams (DFDs): objects, associations,
and activities
Fundamentals of Information Systems, Fourth Edition 38
Data Analysis (continued)
Figure 8.12: Data and Activity Modeling (a) An entity-relationship diagram
Fundamentals of Information Systems, Fourth Edition 39
Data Analysis (continued)
Figure 8.12: Data and Activity Modeling (b) A data-flow diagram
Fundamentals of Information Systems, Fourth Edition 40
Data Analysis (continued)
Figure 8.12: Data and Activity Modeling (c) A semantic description of the business process
Fundamentals of Information Systems, Fourth Edition 41
Requirements Analysis
• Determines user, stakeholder, and organizational needs through the following techniques:– Asking directly: best for stable systems– Critical success factors: asks for critical factors in
interviewee’s area – IS plan: translates strategic plan into initiatives– Requirements analysis tools: CASE tools
Fundamentals of Information Systems, Fourth Edition 42
Requirements Analysis (continued)
Figure 8.13: Converting Organizational Goals into Systems Requirements
Fundamentals of Information Systems, Fourth Edition 43
Object-Oriented Systems Analysis
• Identifying problems or potential opportunities
• Identifying key participants and collecting data
• Uses classes and generalization/specialization hierarchies instead of data-flow diagrams and flowcharts
Fundamentals of Information Systems, Fourth Edition 44
Object-Oriented Systems Analysis (continued)
Figure 8.14: Generalization/Specialization Hierarchy Diagram for Single and Tandem Kayak Classes
Fundamentals of Information Systems, Fourth Edition 45
The Systems Analysis Report
• Systems analysis report should cover:– Strengths and weaknesses of the existing system
from a stakeholder’s perspective– User/stakeholder requirements for the new system
(also called the functional requirements)– Organizational requirements for the new system– Description of what the new information system
should do to solve the problem
Fundamentals of Information Systems, Fourth Edition 46
Systems Design
• Answers the question “How will the information system solve a problem?”
• Has two dimensions: logical and physical
• Logical design: description of the functional requirements of a system
• Physical design: specification of the characteristics of the system components necessary to put the logical design into action
Fundamentals of Information Systems, Fourth Edition 47
Object-Oriented Design
• Design key objects and classes of objects in the new or updated system– Consideration of the problem domain, the operating
environment, and the user interface– Consideration of the sequence of events that must
happen for the system to function correctly
• Scenario: sequence of events– Can be diagrammed in a sequence diagram
Fundamentals of Information Systems, Fourth Edition 48
Object-Oriented Design (continued)
Figure 8.16: A Sequence Diagram to Add a New KayakItem Scenario
Fundamentals of Information Systems, Fourth Edition 49
Generating Systems Design Alternatives
• Request for proposal (RFP): document that specifies in detail required resources such as hardware and software
• Financial options– Purchasing– Leasing– Renting
Fundamentals of Information Systems, Fourth Edition 50
Generating Systems Design Alternatives (continued)
• Evaluating and Selecting a Systems Design– Preliminary evaluation
• To dismiss unwanted proposals
• Begins after all proposals have been submitted
– Final evaluation• Detailed investigation of the proposals offered by the
vendors remaining after the preliminary evaluation
Fundamentals of Information Systems, Fourth Edition 51
The Design Report
• Design report: primary result of systems design, reflecting the decisions made and preparing the way for systems implementation
• System specifications include technical description of the following:– System outputs, inputs, and user interfaces– Hardware, software, databases,
telecommunications, personnel, and procedure components and the way these components are related
Fundamentals of Information Systems, Fourth Edition 52
The Design Report (continued)
Figure 8.18: A Typical Table of Contents for a Systems Design Report
Fundamentals of Information Systems, Fourth Edition 53
Systems Implementation
Figure 8.19: Typical Steps in Systems Implementation
Fundamentals of Information Systems, Fourth Edition 54
Acquiring Hardware from an IS Vendor
• IS vendor: company that offers hardware, software, telecommunications systems, databases, IS personnel, and/or other computer-related resources
• Buying computer hardware
• Leasing computer hardware
• Renting computer hardware
• “Pay-as-you-go,” “on-demand,” or “utility” computing
Fundamentals of Information Systems, Fourth Edition 55
Acquiring Software: Make or Buy?
• Make-or-buy decision: decision regarding whether to obtain software from external or internal sources
• Choices include: – Purchase software externally– Develop software in-house – Used a blend of external and internal software
development– Rent software
Fundamentals of Information Systems, Fourth Edition 56
Acquiring Database and Telecommunications Systems
• Databases and telecommunications systems require a blend of hardware and software
• New hardware is acquired from an IS vendor
• New or upgraded software might be purchased or developed in-house
Fundamentals of Information Systems, Fourth Edition 57
User Preparation
• Process of readying managers, decision makers, employees, other users, and stakeholders for new systems
• Provide users with proper training
Fundamentals of Information Systems, Fourth Edition 58
IS Personnel: Hiring and Training
• Personnel that might be needed for the new system– IS manager– Systems analysts– Computer programmers– Data-entry operators
• Training programs should be conducted for the IS personnel who will be using the computer system
Fundamentals of Information Systems, Fourth Edition 59
Site Preparation
• Preparation of the location of a new system
• Making room for equipment
• Special wiring and air conditioning
• Special floor
• Security system
• Additional power circuits
Fundamentals of Information Systems, Fourth Edition 60
Data Preparation
• Also called data conversion
• Ensures all files and databases are ready to be used with new computer software and systems
Fundamentals of Information Systems, Fourth Edition 61
Installation
• Physically placing the computer equipment on the site and making it operational
• Normally the manufacturer is responsible for installing computer equipment
• Someone from the organization (usually the IS manager) should oversee the process
Fundamentals of Information Systems, Fourth Edition 62
Testing
• Unit testing: testing of individual programs
• System testing: testing the entire system of programs
• Volume testing: testing the application with a large amount of data
• Integration testing: testing all related systems together
• Acceptance testing: conducting any tests required by the user
Fundamentals of Information Systems, Fourth Edition 63
Start-Up
• Process of making the final tested information system fully operational
• Approaches– Direct conversion (plunge, direct cutover): stopping
the old system and starting the new one on a given date
– Phase-in approach (piecemeal): slowly replacing old system components with new system components
– Pilot start-up: run new system with one group of users
– Parallel start-up: running old and new systems together for a period of time
Fundamentals of Information Systems, Fourth Edition 64
User Acceptance
• User acceptance document: formal agreement signed by the user that states that a phase of the installation or the complete system is approved– Legal document that removes or reduces IS vendor’s
liability
Fundamentals of Information Systems, Fourth Edition 65
Systems Operation and Maintenance
• Systems operation: use of a new or modified system– Help desk provides support
• Systems maintenance: checking, changing, and enhancing the system to make it more useful in achieving user and organizational goals– Difficult and costly for legacy systems
Fundamentals of Information Systems, Fourth Edition 66
Systems Review
• Process of analyzing systems to make sure that they are operating as intended– Often compares the performance and benefits of the
system as it was designed with the actual performance and benefits of the system in operation
• Event-driven review: triggered by a problem or opportunity such as an error, a corporate merger, or a new market for products
• Time-driven review: performed after a specified amount of time
Fundamentals of Information Systems, Fourth Edition 67
Systems Review (continued)
Table 8.4: Examples of Review Types
Fundamentals of Information Systems, Fourth Edition 68
Summary
• Information systems planning: translating strategic and organizational goals into systems development initiatives
• Common systems development life cycles: traditional, prototyping, rapid application development (RAD), and end-user development
• Phases of traditional systems development life cycle: systems investigation, systems analysis, systems design, systems implementation, and systems maintenance and review
Fundamentals of Information Systems, Fourth Edition 69
Summary (continued)
• Systems investigation: problems and opportunities are identified and considered in light of the goals of the business
• Systems analysis: study of existing systems and work processes to identify strengths, weaknesses, and opportunities for improvement
• Systems design: defines how the information system will do what it must do to obtain the problem solution
Fundamentals of Information Systems, Fourth Edition 70
Summary (continued)
• Systems implementation: creation or acquisition of various system components detailed in the systems design, assembling them, and placing the new or modified system into operation
• Systems maintenance and review: ensures that the system operates as intended and modifies the system so that it continues to meet changing business needs