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
2
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
3
4. Information System Components
● Hardware
● Software
– System software
– Network operating system
– Application software
– Enterprise applications
– Horizontal system
– Vertical system
4
5. Information System Components
● Data
– Is the raw material that an information system
transforms into useful information
– Tables
– Linking
5
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
6
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
7
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
8
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
9
10. How Business Uses Information Systems
● Enterprise computing systems
– Support company-wide operations and data
management requirements
– Enterprise resource planning (ERP)
10
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
11
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
12
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
13
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
14
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
15
16. Information System Users and Their
Needs
● Top managers
● Middle Managers and Knowledge Workers
● Supervisors and Team Leaders
● Operational Employees
● Strategic plans
16
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
17
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
18
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
19
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
20
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
21
22. Systems Development Methods
● Structured Analysis
– Uses a set of process models to describe a system
graphically
– Systems development life cycle (SDLC)
22
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
23
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)
24
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
25
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
26
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
27
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
28
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
29
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
30
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
31
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
32
33. Information Technology Department
● The information technology (IT) department
develops and maintains a company s
information systems
● The IT group provides technical support
33
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
34
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
35
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
36
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
37
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
38
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
39
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
40
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)
41
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
42
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
43
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
44
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
45
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)
46
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
47
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
48