1. Systems Analysis & Design!
Sixth Edition!
SYSTEM DESIGN
TOPICS

2. Objectives
● Identify various types of information systems
and explain who uses them
● Explain systems development tools, including
modeling, prototyping, and CASE tools
● Distinguish between structured analysis and
object-oriented methodology
● Describe the systems development life cycle
● Discuss the role of the information
technology department and the systems
analysts who work there
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3. Information System Components
● A system is a set
of related
components that
produces specific
results
● A mission-critical
system is one that
is vital to a
company s
operations
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4. Information System Components
● Hardware
● Software
– System software
– Network operating system
– Application software
– Enterprise applications
– Horizontal system
– Vertical system
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5. Information System Components
● Data
– Is the raw material that an information system
transforms into useful information
– Tables
– Linking
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6. Information System Components
● Processes
– Define the tasks and business functions that users,
managers, and IT staff members perform to achieve
specific results
● People
– Users, or end users, are the people who interact with
an information system, both inside and outside the
company
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7. Impact of the Internet
● E-Commerce (I-Commerce)
● B2C (Business-to-Consumer)
● B2B (Business-to-Business)
– EDI, XML, HTML
● Web-Based Development
– WebSphere, .NET
– Web services
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8. How Business Uses Information
Systems
● In past, IT managers divided systems into
categories based on the user group the system
served
– Office systems
– Operational systems
– Decision support systems
– Executive information systems
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9. How Business Uses Information
Systems
● Today, it makes more sense to identify a
system by its functions, rather than by users
– Enterprise computing systems
– Transaction processing systems
– Business support systems
– Knowledge management systems
– User productivity systems
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10. How Business Uses Information Systems
● Enterprise computing systems
– Support company-wide operations and data
management requirements
– Enterprise resource planning (ERP)
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11. How Business Uses Information Systems
● Transaction
processing systems
– Efficient because they
process a set of
transaction-related
commands as a group
rather than individually
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12. How Business Uses Information Systems
● Business support
systems
– Provide job-related
information to users at
all levels of a company
– Management
information systems
(MIS)
– What-if
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13. How Business Uses Information Systems
● Knowledge management systems
– Called expert systems
– Simulate human reasoning by combining a
knowledge base and inference rules
– Many use fuzzy logic
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14. How Business Uses Information Systems
● User productivity systems
– Technology that improves productivity
– Groupware
● Information systems integration
– Most large companies require systems that combine
transaction processing, business support, knowledge
management, and user productivity features
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15. Information System Users and Their
Needs
● A systems analyst must
understand the
company s
organizational model in
order to recognize who
is responsible for
specific processes and
decisions and to be
aware of what
information is required
by whom
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16. Information System Users and Their
Needs
● Top managers
● Middle Managers and Knowledge Workers
● Supervisors and Team Leaders
● Operational Employees
● Strategic plans
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17. Systems Development Tools and
Techniques
● Systems analysts must know how to use a
variety of techniques such as modeling,
prototyping, and computer-aided systems
engineering tools to plan, design, and
implement information systems
● Systems analysts work with these tools in a
team environment
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18. Systems Development Tools and
Techniques
● Modeling
– Used to describe and simplify an information system:
– Business model
– Requirements model
– Data model
– Object model
– Network model
– Process model
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19. Systems Development Tools and
Techniques
● Prototyping
– Prototype
– Speeds up the development process significantly
– Important decisions might be made too early
– Can be an extremely valuable tool
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20. Systems Development Tools and
Techniques
● Computer-Aided Systems Engineering
(CASE) Tools
– Framework for systems development and support a
wide variety of design methodologies
– CASE tools
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21. Systems Development Methods
● Structured analysis and object-oriented
analysis are both popular methodologies for
developing computer-based information
systems
● A systems analyst should understand the
alternative methodologies and their individual
strengths and weaknesses
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22. Systems Development Methods
● Structured Analysis
– Uses a set of process models to describe a system
graphically
– Systems development life cycle (SDLC)
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23. Systems Development Methods
● Object-oriented (O-O) analysis
– O-O analysis combines data & processes into objects
– Object is a member of a class
– Class is a collection of similar objects
– Objects possess properties
– Methods change an object’s properties
– Messages request specific behavior or information
from another object
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24. Systems Development Methods
● Joint Application Development and Rapid
Application Development
– JAD – Team based fact finding
– RAD – compressed version of the entire process
● Other development methodologies
– Microsoft Solutions Framework (MSF)
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25. The Systems Development Life Cycle
● SDLC used to plan and manage the systems
development process
● It includes the following steps:
– Systems planning phase
– Systems analysis phase
– Systems design phase
– Systems implementation phase
– Systems operation, support, and security phase
– Deliverable or end product
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26. The Systems Development Life Cycle
● Traditionally pictured as a waterfall model,
but is also presented as an interactive model
depicting real world practice and the constant
dialog among users, managers, and systems
developers
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27. The Systems Development Life Cycle
● Systems planning (preliminary
investigation )
– Purpose is to identify the nature and scope of the
business opportunity or problem
– Systems request – begins the process & describes
problems or desired changes
– Systems planning includes preliminary investigation
whose key part is a feasibility study
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28. The Systems Development Life Cycle
● Systems Analysis
– Purpose is to build a logical model of the new system
– First step is requirements modeling, where you
investigate business processes and document what the
new system must do
– Second step is data and process modeling
– Third step is object modeling
– Fourth step is transition to system design
– End product is the system requirements document
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29. The Systems Development Life Cycle
● Systems Design
– Purpose is to create a blueprint that will satisfy all
documented requirements
– Identify all outputs, inputs, and processes
– Avoid misunderstanding through manager and user
involvement
– End product is systems design specification
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30. The Systems Development Life Cycle
● Systems Implementation
– New system is constructed
– Write, test, & document programs
– File conversion occurs
– Users, managers, IT staff trained to operate and
support the system
– Systems evaluation performed
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31. The Systems Development Life Cycle
● Systems operation, support, and security
– New system supports operations
– Maintenance changes correct errors or meet
requirements
– Enhancements increase system capability
– Well-designed system will be secure, reliable,
maintainable, and scalable
– SDLC ends with system replacement
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32. Systems Development Guidelines
– Planning
– Involve users throughout the development process
– Listening is very important
– Create a time table with major milestones
– Identify interim checkpoints
– Remain flexible
– Develop accurate cost and benefit information
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33. Information Technology Department
● The information technology (IT) department
develops and maintains a company s
information systems
● The IT group provides technical support
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34. Information Technology Department
● Application Development
– Team may include users, managers and IT staff
members
● Systems Support and Security
– Provides hardware and software support
● User Support
– Provides users with technical information, training,
and productivity support
– Help desk
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35. Information Technology Department
● Database Administration
– Database design, management, security, backup, and
user access
● Network Administration
– Includes hardware and software maintenance,
support, and security
● Web Support
– Design and construction of Web pages and presence
– Important for e-commerce
– Webmaster
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36. The Systems Analyst Position
● A systems analyst investigates, analyzes,
designs, develops, installs, evaluates, and
maintains a company s information systems
● On large projects, the analyst works as a
member of an IT department team
● Smaller companies often use consultants to
perform the work
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37. Summary
● IT is a combination of hardware and
software that support business
● The essential components of an information
system are hardware, software, data,
processes, and people
● Companies are product-oriented, service-
oriented, or a combination of the two
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38. Summary
● Organization structure usually includes
levels. Each level has different responsibilities
and information needs
● Systems analysts use modeling, prototyping,
and CASE tools. Modeling produces a
graphical representation of the process,
prototyping involves creation of an early
working model, and CASE tools assist in
various systems development tasks
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39. Summary
● The Systems Development Life Cycle
(SDLC) consists of five phases: systems
planning, systems analysis, systems design,
systems implementation, and systems
operation, support, and security
● Systems analysts need a combination of
technical and business knowledge, analytical
ability, and communication skills
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40. TOPICS
1- OBJECT MODELING
2- TRANSITION TO SYSTEMS DESIGN
SYSTEM DESIGN
3- USER INTERFACE, INPUT AND OUTPUT DESIGN
4. DATA DESIGN
5. APPLICATION ARCHITECTURE
SYSTEM IMPLEMENTATION
6. APPLICATION DEVELOPMENT
7. INSTALLATION AND EVALUTION
SYSTEM OPERATION AND SUPPORT
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41. PHASE 2
SYSTEMS ANALYSIS
● CHAPTER 5
OBJECT MODELING
1- OBJECT-ORIENTED TERMS AND
CONCEPTS
2- RELATIONSHIPS AMONG OBJECTS
AND CLASSES
3- OBJECT MODELING WITH THE
UNIFIED MODELING LAGUAGE (UML)
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42. PHASE 2
SYSTEMS ANALYSIS
● CHAPTER 6
TRANSITION TO SYSTEMS DESIGN
1- EVALUATING SOFTWARE ALTERNATIVES
2- STEPS IN EVALUATING AND PURCHASING
SW PACKAGES
3- COMPLETION OF SYSTEMS ANALYSIS
4- TRANSITION TO SYSTEM DESIGN
5- PROTOTYPING
6- DESIGNING AND USING CODES
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43. PHASE 3
SYSTEMS DESIGN
● CHAPTER 7
USER INTERFACE, INPUT DESIGN
AND OUTPUT DESIGN
1- USER INTERFACE DESIGN
2- INPUT DESIGN
3- OUTPUT DESIGN ISSUES
4- PRINTED OUTPUT
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44. PHASE 3
SYSTEMS DESIGN
• CHAPTER 8
DATA DESIGN
● 1- DATA DESIGN CONCEPTS
● 2- DATA DESIGN TERMINOLOGY
● 3- DATA RELATIONSHIPS (E-R)
● 4- NORMALIZATION
● 5- STEPS IN DATABASE DESIGN
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45. PHASE 3
SYSTEMS DESIGN
• CHAPTER 9
APPLICATION ARCHITECTURE
1- CLIENT/SERVER ARCHITECTURE
2- PROCESSING METHODS (ON-LINE, BATCH AND
COMBINATION)
3- NETWORK MODELS
4- SYSTEM MANAGEMENT AND SUPPORT
( PERFORMANCE, SECURITY, BACKUP,
FAULT,..)
5- SYSTEM DESIGN COMPLETION
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46. PHASE 4
SYSTEMS IMPLEMENTATION
● CHAPTER 10
APPLICATION DEVELOPMENT
1- QUALITY ASSURANCE
2- STRUCTURED APPLICATION DEVELOPMENT
(STRUCTURE CHARTS)
3- CODING
4- OBJECT-ORIENTED APPLICATION DEV.
5- TESTING THE APPLICATION (UNIT,
INTEGRATION AND SYSTEM)
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47. PHASE 4
SYSTEMS IMPLEMENTATION
● CHAPTER 11
INSTALATION AND EVALUATION
● 1- OPERATIONAL AND TEST ENVIROMENTAL
● 2- TRAINING
● 3- SYTEM CHANGOVER
● 4- DATA CONVERSION
● 5- FINAL REPORT TO MANAGEMENT
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48. PHASE 5
SYSTEMS OPERATION AND SUPPORT
● CHAPTER 12
– SYSTEMS OPERATION AND
SUPPORT
● 1- USER SUPPORT ACTIVITIES
● 2- MAINTENANCE ACTIVITIES (CORRECTIVE,
ADAPTIVE, PERFECTIVE AND PREVENTIVE)
● 3-MANAGING SYSTEM PERFOMANCE
● 4- SYSTEM OBSOLESCENCE
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49. ● THANKS FOR ALL
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