1 The Impact of Information Technology The Role of Systems Analysis and Design – Systems Analysis and Design • Step-by-step process for developing high-quality information systems – Systems Analyst • Plan, develop, and maintain information systems
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The Impact of Information Technology
The Role of Systems Analysis and Design– Systems Analysis and Design
• Step-by-step process for developing high-quality information systems
– Systems Analyst• Plan, develop, and maintain
information systems
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The Impact of Information Technology
Who develops Information Systems?– In-house applications– Software packages– Internet-based application services – Outsourcing– Custom solutions– Enterprise-wide software strategies– How versus What
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Figure 1-5
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
Data consists of basic facts that are the system’s raw material
Figure 1-6
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Figure 1-7
Information System Components
Information is data that has been transformed into output that is valuable to users
Information systems have five key components: hardware, software, data, processes, and people
Figure 1-8
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Hardware – Is the physical layer of the
information system– Moore’s Law
Information System Components
Figure 1-9For more information about Moore’s Law visit scsite.com/sad7e/more, locate Chapter 1 and then the Moore’s Law link.
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Information System Components
Software– System software– Application software – Enterprise applications– Horizontal system– Vertical system– Legacy systems
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Information System Components
Data – Is the raw material that an
information system transforms into useful information
– Tables– Linking
Figure 1-10
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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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Understanding The Business
Business Process Modeling Business Profile Business Models
– Business model– Business process– Business process reengineering (BP
R)
Figure 1-11
Figure 1-12
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Understanding The Business
New Kinds of Companies– Production-oriented – Service-oriented– Internet-dependent– Dot-com (.com)– Brick-and-mortar
Figure 1-13
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Impact of the Internet
E-Commerce or I-Commerce B2C (Business-to-Consumer) B2B (Business-to-Business)
– EDI– Extensible markup language (XML)– Supplier relationship management (
SRM)
Figure 1-14For more information aboutE-commerce visit scsite.com/sad7e/more, locate Chapter 1 and then the Electronic commerce link.
For more information about XML visit scsite.com/sad7e/more, locate Chapter 1 and then the Extensible Markup Language link..
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Impact of the Internet
Web-Based System Development– WebSphere– .NET– Web services
Figure 1-15
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How Business Uses InformationSystems
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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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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How Business Uses Information Systems
Enterprise computing systems– Support company-wide operations
and data management requirements
– Enterprise resource planning (ERP)
Figure 1-16For more information about Enterprise Resource Planning visit scsite.com/sad7e/more, locate Chapter 1 and then the Enterprise Resource Planning link.
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How Business Uses Information Systems
Transaction processing systems– Efficient because they process a set
of transaction-related commands as a group rather than individually
Figure 1-17
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How Business Uses Information Systems
Business support systems– Provide job-related information to
users at all levels of a company– Management information systems (
MIS)– Radio frequency identification (RFID
)– What-if
Figure 1-18
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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
Figure 1-29For more information about Knowledge Management systems visit scsite.com/sad7e/more, locate Chapter 1 and then the Knowledge Management systems link.
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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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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.
Figure 1-20
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Information System Users and Their Needs
Top managers– Strategic plans
Middle Managers and Knowledge Workers
Supervisors and Team Leaders Operational Employees
– Empowerment
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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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Systems Development Tools and Techniques
Modeling– Business model– Requirements model– Data model– Object model– Network model– Process model
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Systems Development Tools and Techniques
Prototyping– Prototype– Speeds up the development
process significantly– Important decisions might be made
too early, before business or IT issues are thoroughly understood
– Can be an extremely valuable tool
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Systems Development Tools and Techniques
Computer-Aided Systems Engineering (CASE) Tools– Also called
computer-aided software engineering
– CASE tools
Figure 1-21
Figure 1-22For more information about CASE tools visit scsite.com/sad7e/more, locate Chapter 1 and then the CASE tools link.
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Systems Development Methods
The most popular alternatives are structured analysis, which is a traditional method that still is widely used, and object-oriented analysis (O-O), which is a newer approach that many analysts prefer
The important thing is for a systems analyst to understand the various methods and the strengths and weaknesses of each approach
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Systems Development Methods
Structured Analysis– Systems development life cycle (SD
LC)– Predictive approach– Uses a set of process models to
describe a system graphically– Process-centered technique
Figure 1-23
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Systems Development Methods
Object-oriented Analysis– O-O analysis combines data &
processes into objects– Object is a member of a class– Objects possess properties– Methods change an object’s
properties– A message requests specific
behavior or information from another object
Figure 1-24
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Planning and Modeling a Systems Development Project
In addition to selecting a development method, system developers also must create a plan or model for the many tasks that will be required
Typically, the development team will use project management tools to help achieve the end result
Figure 1-25
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Planning and Modeling a Systems Development Project
Comparison of Predictive and Adaptive Models– The SDLC usually is referred to as
the waterfall model– Interactive model– Adaptive or iterative approaches– Spiral model
Figure 1-26
Figure 1-27
Figure 1-28
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Planning and Modeling a Systems Development Project
The SDLC Waterfall Model– Deliverable or end product– Disadvantage in the built-in structure
of the SDLC, because the waterfall model does not emphasize interactivity among the phases
– This criticism can be valid if the SDLC phases are followed too rigidly
– However, adjacent phases usually interact
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Planning and Modeling a Systems Development Project
The SDLC Waterfall Model– Usually includes five steps
• Systems planning• Systems analysis• Systems design• Systems implementation• Systems operation, support, and
security
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Planning and Modeling a Systems Development Project
Systems planning– Systems planning phase– Systems request – begins the
process & describes problems or desired changes
– Purpose of this phase is to perform a preliminary investigation whose key part is a feasibility study
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Planning and Modeling a Systems Development Project
Systems Analysis– Systems analysis phase– First step is requirements modeling,
where you investigate business processes and document what the new system must do
– End product is the System requirements document
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Planning and Modeling a Systems Development Project
Systems Design– Systems design phase– Identify all outputs, inputs, and
processes– Avoid misunderstanding through
manager and user involvement– End product is
system design specification
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Planning and Modeling a Systems Development Project
Systems Implementation– Systems implementation phase– New system is constructed– Write, test, & document programs– File conversion occurs– Users, managers, IT staff trained to
operate and support the system– System evaluation performed
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Planning and Modeling a Systems Development Project
Systems Operation, Support, and Security– Systems Operation, Support, and S
ecurity phase– A well-designed system must be
secure, reliable, maintainable, and scalable
– After several years of operation, systems need extensive changes
– SDLC ends with system replacement
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Planning and Modeling a Systems Development Project
Adaptive Methods and Models– Attempt to develop a system
incrementally, by building a series of prototypes and constantly adjusting them to user requirements
– Extreme Programming (XP)– Analysts should recognize that
these approaches have advantages and disadvantages
Figure 1-29 Figure 1-30
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Planning and Modeling a Systems Development Project
Joint Application Development and Rapid Application Development Methods and Models– Joint application development (JAD)– Rapid application development (RA
D)
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Planning and Modeling a Systems Development Project
Other Development Methods and Models– Rational Unified Process (RUP®)– Microsoft Solutions Framework
(MSF)
Figure 1-31For more information about Microsoft Solutions Framework visit scsite.com/sad7e/more, locate Chapter 1 and then the Microsoft Solutions Framework link.
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Planning and Modeling a Systems Development Project
The Importance of Project Management– Regardless of the development
strategy, people, tasks, timetables, and expenses must be managed effectively
– Complex projects can involve dozens of people, hundreds of tasks, and many thousands of dollars
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Systems Development Guidelines
Stick to a plan Involve the users throughout the
development process Listening is very important Use project management tools to
identify tasks and milestones Remain flexible Develop accurate cost and benefit
information
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Information Technology Department
The information technology (IT) department develops and maintains a company’s information systems.
The IT group provides technical support
Figure 1-33
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Information Technology Department
Application Development– Team may include users, managers
and IT Staff members Systems Support and Security
– Deployment team User Support
– Help desk or information center (IC)
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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– Webmasters
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Information Technology Department
Quality Assurance (QA)– Reviews and tests all applications
and systems changes to verify specifications and software quality standards
– Is a separate unit that reports directly to IT management
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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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The Systems Analyst Position
Responsibilities– Translate business requirements
into practical IT projects to meet needs
Required Skills and Background– Solid communication skills and
analytic ability
Figure 1-34
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The Systems Analyst Position
Certification– Professional credential
Career Opportunities– Job titles– Company organization– Company size– Corporate culture– Salary, location, and future growth