Today’s Topics  Chapter 2: Internet and World Wide Web  Chapter 3: Wired and Wireless Technology

Chapter 2 The Internet & World Wide Web

How the Internet Works  Internet: a global computer network  Interoperability: a key success to the Internet  Internet Service Provider (ISP): a company that sells Internet accounts Netzero, SBC, Charter, AT&T, Verizon Netzero, SBC, Charter, AT&T, Verizon  Online Service: a for-profit firm that provides a proprietary network AOL, EarthLink, MSN AOL, EarthLink, MSN

Internet Accesses  Dial-Up Access: slow, not reliable but lowest cost  Digital Subscriber Line (DSL): medium, reliable but high cost  Cable and Satellite Access: fast, reliable but high cost  Satellite Access: medium, reliable, but high cost  Network Access: fast, available, and usually free to users

World Wide Web  WWW: a portion of the Internet that contains billions of documents  World Wide Web Consortium (W3C): an organization issuing standards related to all aspects of the Web  Web Site: a location that is accessible from the Internet and makes web pages available

World Wide Web  Web Page: any document on a Web site that includes text, graphics, sound, or video  Home Page or Index Page: a default page that is displayed automatically when entering a site at the top level  Hypertext: a method of preparing and publishing text that is suited to be read with a computer

World Wide Web  Hyperlink or Link: a word that can be clicked to bring another document into view  Distribute Hypermedia System: a network- based content development system that uses multimedia resources as a mean of navigation or illustration  Dead or Broken Link: a link to documents that have disappeared

World Wide Web  Web Browser: a program that displays a Web document IE, Netscape Navigator, Mosaic IE, Netscape Navigator, Mosaic  Uniform Resource Locator (URL): a string of characters that precisely identifies an Internet resource’s type and location Protocol Protocol Server Server Path Path Resource Name Resource Name

URL

URL  Hypertext Transfer Protocol (HTTP): the Internet standard that supports the exchange of information on the Web  Domain Name System (DNS): an Internet address system that includes letters as well as numbers  Domain Name Registration: a process for individuals and organizations to register a domain name

URL  Top-Level Domain (TLD) Name: the last part of the domain name that indicates the type of organization in which the computer is located.com,.edu,.gov,.org.com,.edu,.gov,.org

World Wide Web  Downloading: transferring a document or file from another computer to your computer  Uploading: transferring a document or file from your computer to another computer

Finding Information on the Web  Search Engine: a searching database that claims to index the full Web Google, MSN, Yahoo, AltaVista Google, MSN, Yahoo, AltaVista  Specialized Search Engine: a searching database to index specialized information Careerbuilder, Travelocity Careerbuilder, Travelocity  Portal: a gateway that provides a conveniently organized subject guide to various Internet content MSN MSN

Search Techniques  Search Operators: symbols or words used for advanced searches Inclusion and Exclusion Operators ( + and -) Inclusion and Exclusion Operators ( + and -) Wildcards (*) Wildcards (*) Phrase Searches (“ ”) Phrase Searches (“ ”) Boolean Searches (AND, OR and NOT) Boolean Searches (AND, OR and NOT) Parentheses Parentheses

Internet Services  a software application to send and receive messages via networks  Attachment: any computer file that is included with an message  Address: a unique cyberspace identity for a particular recipient composed of a user sign, name of the server hosting the service, and the top level domain  Spam: an unsolicited advertising

Internet Services  Instant Messaging (IM) System: a system that allows Internet users to exchange near real-time messages  Internet Relay Chat (IRC): an Internet service that allows Internet users to join chat groups, using text-based conversation  File Transfer Protocol (FTP): a way that files can be transferred over the Internet

Internet Services  Usenet: a worldwide computer-based discussion system  Newsgroups: discussion groups devoted to a single topic  Listserv: electronic mailing list

Chapter 3 Wired & Wireless Communication

Communications  Communication: process of electronically sending and receiving messages between two points  Communication Channel: path through which messages are passed from one location to the next - analog signal: phone - digital signal : computer

Communications  Bandwidth: amount of data that can be transmitted through a given communication channel, measured in bits per second (bps)  Broadband: any transmission medium that transports high volumes of data at high speeds  Modem: communications device used to transmit data over telephone lines Modulation: transformation from digital to analog Modulation: transformation from digital to analog Demodulation: transformation from analog to digital Demodulation: transformation from analog to digital

Transmission Media  Wired Media Twisted Pair Twisted Pair Coaxial Cable Coaxial Cable Fiber-Optic Cable Fiber-Optic Cable  Wireless Media Infrared Infrared Radio Radio Bluetooth Bluetooth Microwaves Microwaves Satellites Satellites

Wired Communication  Public Switched Telephone Network (PSTN): global telephone system  Last-Mile Problem: inability of home and businesses to access the PSTN’s high- speed fiber-optic cables, along with bottleneck of data on the last mile of phone lines connecting homes and businesses

Last-Mile Technologies  Integrated Services Digital Network (ISDN)  Digital Subscriber Line (DSL)  Coaxial Cable and Cable Modems  Leased Lines: T1, T2, T3  Synchronous Optical Network (SONET)

Convergence  Convergence: merging of disparate objects into new combinations 1G: Analog Cellular Phone 1G: Analog Cellular Phone 2G: Personal Communication Service (PCS) 2G: Personal Communication Service (PCS) Digital Cellular PhoneDigital Cellular Phone Web-Based Device: PDA (Palm Pilot, Blackberry, etc.)Web-Based Device: PDA (Palm Pilot, Blackberry, etc.)

Wired and Wireless Applications  Internet Telephony  Videoconferencing  Whiteboard  Web Cam  Fax Modem  Satellite Radio  Global Positioning System (GPS)