PC Basics CPSC 100 Hardware Software Networking Copyright 2006 Prentice-Hall. All rights reserved. 1 Objectives Identify basic components of a computer (hardware) Gain insight into how computers work (software) Gain insight into how computers talk to each other (networking) Copyright 2006 Prentice-Hall. All rights reserved. 2
Types of Computers Desktop Laptop Personal Digital Assistant Tablet Computer Workstation Dumb Terminal More Copyright 2006 Prentice-Hall. All rights reserved. 3 Hardware vs. Software Hardware is a peripheral or physical part of the computer including: Software is a program or application that runs on the computer. Monitors Printers Drives Keyboards Word Excel PowerPoint FrontPage Copyright 2006 Prentice-Hall. All rights reserved. 4
Computer Organization Central Processing Unit (CPU) Input/Output (I/O) Devices Storage Devices Interface Cards Controller Cards Bus Copyright 2006 Prentice-Hall. All rights reserved. 5 Central Processing Unit The Brain Allows for mathematical or logical operations Assembles & processes information Integrated with millions of components Rated in terms of how many instructions per second it can handle (MHz, GHz) Sometimes more than one CPU (Dual Core, Quad Core) Today, 2 < 4 GHz Copyright 2006 Prentice-Hall. All rights reserved. 6
Input and Output Devices Input transferring data into the computer Output sending the information out Common input devices: Keyboard & Mouse Bar Code reader Common output devices: Monitor Printer Copyright 2006 Prentice-Hall. All rights reserved. 7 Memory and Storage Primary storage for data being processed Secondary storage for results of processing Read-only memory (ROM) Factory programmed with instructions Normally used at startup Random access memory (RAM) Temporary storage for programs Today, 2 < 4 GB Copyright 2006 Prentice-Hall. All rights reserved. 8
Secondary Storage Devices Devices where data can be stored for later use Three main types: Magnetic media floppy disk Optical media compact disc Flash memory used with digital cameras Copyright 2006 Prentice-Hall. All rights reserved. 9 Storage Media Low-cost method to store data Speed is slower Do not require continuous power Measured in megabytes, gigabytes, or terabytes Copyright 2006 Prentice-Hall. All rights reserved. 10
Magnetic Storage Hard Disks Aluminum disk with magnetic material Floppy disks Plastic disk with magnetic material Tape drives Flexible plastic tape with magnetic material Used for software backup Copyright 2006 Prentice-Hall. All rights reserved. 11 Optical Discs CD and DVD are types of optical discs Available as read-only, recordable one-time, or erase and record many times CD-R Record one time, unlimited reading CD-RW Rewritable DVD-ROM Record on two different levels and on both sides Copyright 2006 Prentice-Hall. All rights reserved. 12
Flash Memory Constant power not required Solid state - No moving parts Used in portable electronic devices PDAs Cameras Copyright 2006 Prentice-Hall. All rights reserved. 13 Expansion Cards Built like a small motherboard Integrated circuits and data bus on piece of plastic Used to add new capabilities to computer Offload work from the CPU (Graphics Controller Card) Most common expansion card is a network interface card (NIC) Copyright 2006 Prentice-Hall. All rights reserved. 14
Motherboard and Data Bus Motherboard Connects everything together Data bus Wires on the motherboard Lets components talk to each other Copyright 2006 Prentice-Hall. All rights reserved. 15 Operating System Programming that controls interactions with the computer s various parts (hardware) and the user Acts as a layer between hardware & software Types of Operating Systems: Mac OS Windows UNIX Linux Copyright 2006 Prentice-Hall. All rights reserved. 16
Networking A connection that allows two or more computers to talk to each other Used to share information & resources, control computers Has many benefits & vulnerabilities Copyright 2006 Prentice-Hall. All rights reserved. 17 Types of Networks LAN Local Area Network Restricted to small geographical area Example: Small office network WAN Wide Area Network Could cover the world Example: The Internet Copyright 2006 Prentice-Hall. All rights reserved. 18
Connecting a Network NIC (network interface card) Must be present for each node NIC plugged into an expansion slot or built into the motherboard Most operating systems are equipped with the networking software Copyright 2006 Prentice-Hall. All rights reserved. 19 Client/Server Networks Server Computer to manage the network and all of its devices Client Individual computer on the network requesting services from the server Copyright 2006 Prentice-Hall. All rights reserved. 20
Benefits of Networked Computing Shared hardware Printers and scanners Results in cost savings Offers recovery of desk space Copyright 2006 Prentice-Hall. All rights reserved. 21 Benefits of Networked Computing (Continued) Shared software Purchase of site license Install on server for multiple user access Easier to provide updates and maintenance Copyright 2006 Prentice-Hall. All rights reserved. 22
Benefits of Networked Computing (Continued) Shared Data Data can be updated; reduces multiple copies and overcomes problem of keeping track of changes Multiple access for different users File-by-file permissions can be set for security concerns Databases can be stored on several computers creating a distributed database Copyright 2006 Prentice-Hall. All rights reserved. 23 Benefits of Networked Computing (Continued) Faster communication Enhanced collaboration Increased business opportunities and efficiency Online commerce/sales FAQs Frequently Asked Questions Copyright 2006 Prentice-Hall. All rights reserved. 24
Benefits of Networked Computing (Continued) Educational Benefits Web-based training Content does not require frequent revision Large numbers of people can be trained Would be otherwise expensive or detrimental to the business to gather people together for training Subject matter can be tested online Copyright 2006 Prentice-Hall. All rights reserved. 25 Benefits of Networked Computing (Continued) Online courses Synchronous Everyone working at the same time Asynchronous Occurring at any time Chats Used by synchronous courses Streaming video One-way distribution of video and audio to students from a prerecorded presentation Threaded discussions Students can track comments or questions by category Copyright 2006 Prentice-Hall. All rights reserved. 26
Benefits of Networked Computing (Continued) More efficient meetings Cost savings Copyright 2006 Prentice-Hall. All rights reserved. 27 Risks of Networked Computing Shared hardware and software Abuse/misuse shared resources Not available when needed Unauthorized use of shared data Network failure - non malicous Access to shared information is lost Communication is lost inside and outside the company Shared hardware, such as printers, unavailable Shared software is not available Access to intranet and Internet is lost Denial of Service (DOS) Same as Network Failure Malicious intent (active attack) Copyright 2006 Prentice-Hall. All rights reserved. 28
Other Network Risks Spam Get rich quick! Unwanted mail, often combines w/phishing Phishing Looking for personal information, trick into divulging Spyware Records every keystroke you make (usernames, passwords, account # s) Pop-ups Take you to places you did not want to go Cookies Stores personal info, can be stolen/manipulated Copyright 2006 Prentice-Hall. All rights reserved. 29 Malicious Programs Virus Small program that enters your computer and tricks it into producing copies that are transmitted to other computers Payload Virus program that has a program that might perform functions such as erasing a PC Macro Virus Single name executes several steps for the purpose of destruction Copyright 2006 Prentice-Hall. All rights reserved. 30
Malicious Programs (Continued) Worm Searches for holes in a computer s security Replicates itself, such as by sending out junk mail or flooding targeted servers with requests for services Trojan horse Program claims to do one thing, but instead does something else to damage files Most common in pirated software Copyright 2006 Prentice-Hall. All rights reserved. 31 Malicious Programs (Continued) E-mail bomb Single e-mail message initiates a high number of continuous e-mail messages. Attempts to overwhelm the e-mail service by sheer quantity Spoofing Use of someone s address book to send infected e-mail messages Copyright 2006 Prentice-Hall. All rights reserved. 32
Principles of Network Security Access Control Authenticate Users Privacy/Confidentiality Integrity Non-Repudiation Resource Availability Copyright 2006 Prentice-Hall. All rights reserved. 33 Principles of Network Security Access Control Protect resources/information, make available only to authorized users Authenticate Users Username/Password Biometrics Assists w/access Control Privacy/Confidentiality Keep private information private! Copyright 2006 Prentice-Hall. All rights reserved. 34
Principles of Network Security Integrity Prevent unauthorized changes to information Non-Repudiation After I did something, I can t say that I didn t do it (Proof that I did something) Resource Availability Access to machines/resources/information available when needed Copyright 2006 Prentice-Hall. All rights reserved. 35 Summary Computer Hardware Major Components Internal machine organization Computer Software Applications Operating System between Hardware & Software Computer Networks Connecting to Network Benefits Vulnerabilities Copyright 2006 Prentice-Hall. All rights reserved. 36