McGraw-Hill/Irwin ©2008 The McGraw-Hill Companies, All Rights Reserved
SECTION 5.1SECTION 5.1
HARDWARE AND SOFTWARE
HARDWARE AND SOFTWARE
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INTRODUCTION
• Information technology (IT) - any computer-based tool that people use to work with information and support the information and information-processing needs of an organization– Hardware - consists of the physical devices
associated with a computer system– Software - the set of instructions that the
hardware executes to carry out specific tasks
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HARDWARE BASICS
• Hardware components include:1. Central processing unit (CPU)
2. Primary storage
3. Secondary storage
4. Input device
5. Output device
6. Communication device
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Central Processing Unit
• Central processing unit (CPU) (or microprocessor
• Control unit
• Arithmetic-logic unit (ALU)
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Advances in CPU Design
• Complex instruction set computer (CISC) chip - type of CPU that can recognize as many as 100 or more instructions, enough to carry out most computations directly
• Reduced instruction set computer (RISC) chip - limit the number of instructions the CPU can execute – these are faster than CISC chips.
• Virtualization - a protected memory space created by the CPU allowing the computer to create virtual machines
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Primary Storage
• Primary storage - the computer’s main memory, which consists of the random access memory (RAM), cache memory, and the read-only memory (ROM) that is directly accessible to the CPU
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Primary Storage - RAM
• Random access memory (RAM) - the computer’s primary working memory, in which program instructions and data are stored so that they can be accessed directly by the CPU via the processor’s high-speed external data bus– Volatility – Cache memory
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Primary Storage (ROM)
• Read-only memory (ROM) - the portion of a computer’s primary storage that does not lose its contents when one switches off the power, AKA non-volatile.
• Portable ROM– Flash memory – Memory card– Memory stick
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Secondary Storage
• Older devices use magnetic tape
• Optical mediums use laser technology:– Compact disk-read-only memory (CD-ROM) – Compact disk-read-write (CD-RW) drive– Digital video disk (DVD) – DVD-ROM drive– Digital video disk-read/write (DVD-RW)
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Input Devices
– Manual input devices• Joystick• Keyboard• Microphone• The textbook lists 4 more types
– Automated input devices• Bar code scanner• Digital camera• Magnetic ink character reader• The textbook lists 4 more types.
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Output Devices
• Output device - equipment used to see, hear, or otherwise accept the results of information processing requests – Cathode-ray tube (CRT)– Liquid crystal display (LCD)– Printers– The book forgot to list speakers.
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Communication Devices
• Communication device - equipment used to send information and receive it from one location to another– Dial-up access– Cable– Digital subscriber line– Wireless– Satellite
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COMPUTER CATEGORIES
• Computer categories include:– Personal digital assistant (PDA) – Laptop– Tablet– Desktop– Workstation – Minicomputer – Mainframe computer– Supercomputer
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System Software
– Operating system software – runs everything. • Mac/OS2• Linux• Unix• Windows
– Utility software - provides additional
functionality to the operating system. • Can you give some examples?
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Application Software
• Types of application software – does user tasks.– Browser– Communication– Data management– Desktop publishing– E-mail– Groupware– Presentation graphics– Programming– Spreadsheet– Word processing
McGraw-Hill/Irwin ©2008 The McGraw-Hill Companies, All Rights Reserved
SECTION 5.2SECTION 5.2
Enterprise ArchitectureEnterprise
Architecture
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Backup and Recovery
• Backup - an exact copy of a system’s information
• Recovery - the ability to get a system up and running in the event of a system crash or failure
• What is the difference between – Fault tolerance – Failover
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Infrastructure Architecture
• Flexibility – Changing business needs
• Scalability – Changes in demand volume
• Reliability – Information is correct
• Availability – Percentage of time system is accessible to users.
• Performance – Speed and throughput
• Managed by Capacity planning
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Capacity Planning 1
• Demand will fluctuate
• Capacity should at least match peak demand, not average demand
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Capacity Planning 2
Assume you need 110 GB Capacity. Which setup would you prefer?
100 GBCapacity
100 GBCapacity
40 GBCapacity
40 GBCapacity
40 GBCapacity
40 GBCapacity
Plus backup of
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APPLICATION ARCHITECTURE
• Application architecture - determines how applications integrate and relate to each other
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Web Services
• An Event occurs when a condition exceeds normal limits. It triggers action
Event
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Porter Model – In Class Exercise
• Select a company.
• Analyze its profit potential using the Porter Five Forces model.– Buyer Power– Supplier Power– Substitute Products– Barriers to Entry/Exit– Industry Structure