Transcript Chapter 1 Study Tool
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Chapter 1 Introduction to Systems Analysis and Design
Chapter Objectives
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Discuss the impact of information technology on business Define an information system and explain its components Use profiles and models to understand business functions and operations Understand the impact of the Internet on business Identify various types of information systems and explain who uses them
Chapter Objectives
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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
Introduction
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Companies use information as a weapon in the battle to increase productivity, deliver quality products and services, maintain customer loyalty, and make sound decisions. Information technology can mean the difference between success and Figure 1-1 failure
The Impact of Information Technology
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Information Technology
– Combination of hardware and software products and services that companies use to manage, access, communicate, and share information – A vital asset that must be used effectively, updated constantly, and safeguarded carefully
The Impact of Information Technology
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The Future of IT
– Responsible for half of all productivity growth and a third of all economic growth between 1995-1999
Figure 1-3
The Impact of Information Technology
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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
The Impact of Information Technology Figure 1-4
The Impact of Information Technology
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Who develops Information Systems?
– – – – – – – In-house applications Software packages Internet-based application services Outsourcing Custom solutions Enterprise-wide software strategies How versus What
Information System Components
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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 Information systems have five key components: hardware, software, data, processes, and people Figure 1-6
Information System Components Figure 1-9
Information System Components
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Hardware
– – Everything in the physical layer of the information system Moore’s Law accurately predicted that computer processing power would double every 18 to 24 months
Information System Components
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Software
– – – – – – – System software Network operating system Application software Enterprise applications Horizontal system Vertical system Legacy systems
Information System Components
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Data
– The raw material that an information system transforms into useful information
Figure 1-11
Information System Components
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Processes
– Describe 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
Understanding The Business
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Business Profile
– Overview of a company
Business Models
– Graphical representation of one or more business processes
Figure 1-12
Understanding The Business
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New Kinds of Companies Companies are classified based on their main activities:
– – – – Production-oriented Service-oriented Brick-and-mortar Dot-com (.com)
Figure 1-14
Impact of the Internet
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E-Commerce (I-Commerce)
– Internet-based commerce
B2C (Business-to-Consumer)
– Consumers can go online to purchase a variety of products and services
B2B (Business-to-Business)
– Enables smaller suppliers to contact large customers and allows purchasers to obtain instant information about market prices and availability
Impact of the Internet
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B2B (Business-to-Business)
– EDI • Computer-to-computer transfer of data between companies
Web-Based System Development
– Internet-based systems development is rapidly changing – – WebSphere .NET
How Business Uses Information Systems
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In the 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
How Business Uses Information Systems
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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
How Business Uses Information Systems
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Enterprise computing systems
– Information systems that support company wide operations and data management
Figure 1-17
How Business Uses Information Systems
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Transaction processing systems
– Process data generated by day-to-day business operations
Figure 1-18
How Business Uses Information Systems
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Business support systems
– Provide job-related information to users at all levels of a company – – Management information systems (MIS) What-if
Figure 1-19
How Business Uses Information Systems
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Knowledge management systems
– Simulate human reasoning
Figure 1-20
How Business Uses Information Systems
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User productivity systems
– – Technology that improves productivity Word processing is an example ●
Information systems integration
– Most large companies require systems that combine transaction processing, business support, knowledge management, and user productivity features
Information System Users and Their Needs Figure 1-21
Information System Users and Their Needs
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Top managers Middle Managers and Knowledge Workers Supervisors and Team Leaders Operational Employees
Systems Development Tools and Techniques
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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
Systems Development Tools and Techniques
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Modeling
– A systems analyst can describe and simplify an information system by using a set of business, data, object, and process models.
Systems Development Tools and Techniques
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Prototyping
– – Early working version of an information system Speeds up the development process significantly – Can be an extremely valuable tool
Systems Development Tools and Techniques
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Computer-Aided Systems Engineering (CASE) Tools
– CASE uses powerful software to help systems analysts develop and maintain information systems
Figure 1-22
Systems Development Methods
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Structured Analysis
– – traditional systems development technique Uses the systems development life cycle to plan, analyze, design, implement, and support an information system
Figure 1-25
Systems Development Methods
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Object-oriented (O-O) analysis
– combines data and the processes that act on the data into things called objects – Systems analysts use O-O to model real-world business processes and operations
Systems Development Methods
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Object-oriented (O-O) analysis Figure 1-26
Systems Development Methods
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Joint Application Development and Rapid Application Development
– JAD – Team based fact finding – RAD – compressed version of the entire process
Systems Development Methods
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Other development methodologies
– In addition to structured analysis and O-O methodologies, you might encounter other systems development techniques – Microsoft Solutions Framework (MSF) documents the experience of its own IT teams
The Systems Development Life Cycle
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SDLC used to plan and manage the systems development process.
It includes the following steps:
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Systems planning Systems analysis Systems design Systems implementation Systems operation and support
The Systems Development Life Cycle Figures 1-28 & 1-29
The Systems Development Life Cycle
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Systems planning
– – 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
The Systems Development Life Cycle
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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 – End product is the System requirements document
The Systems Development Life Cycle
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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 system design specification
The Systems Development Life Cycle
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Systems Implementation
– – – – 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
The Systems Development Life Cycle
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Systems Operation and Support
– – IT staff maintains and enhances the system Maintenance changes correct errors and adapt to changes in the environment – Enhancements provide new features and benefits – Well-designed system will be reliable, maintainable, and scalable
The Systems Development Life Cycle
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Systems Development Guidelines
– – – – – – Stick to a plan Involve users Identify milestones Establish checkpoints Be flexible Provide accurate and reliable cost and benefit information
Information Technology Department
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The information technology (IT) department develops and maintains a company’s information systems Figure 1-30
Information Technology Department
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Application Development
– Team may include users, managers and IT Staff members
Systems Support
– Provides hardware and software support
User Support
– Provides users with technical information, training, and productivity support
Information Technology Department
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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
The Systems Analyst Position
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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
The Systems Analyst Position
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Responsibilities Required Skills and Background Figure 1-31
The Systems Analyst Position
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Certification
– Professional credential
Career Opportunities
– Job titles – – – – Company organization Company size Corporate culture Salary, location, and future growth
Chapter Summary
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IT is a combination of hardware, software, and telecommunications systems that support business The essential components of an information system are hardware, software, data, processes, and people Companies are production oriented, service oriented, or a combination of the two.
Chapter Summary
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Based on their function and features, information systems are identified Organization structure usually includes levels Systems analyst use modeling, prototyping, and CASE tools Various development methodologies exist, including structured analysis and object-oriented analysis
Chapter Summary
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An IT department develops, maintains and operates a company’s information systems Systems analysts need a combination of technical and business knowledge, analytical ability, and communication
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Chapter 1 Complete