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Understanding the Internet Chapter 1 Learn how to… • Define the Internet, describe how large the Internet is, and compare its explosive growth. • Identify the most popular Internet services. • Describe underlying concepts of the Internet. • Define how the Internet impacts everyday life. • Provide a brief history of the Internet. • Describe efforts under way to improve the Internet. CIW • CIW stands for Certified Internet Webmaster. • To certify, you have to pass an exam proctored by an independent testing firm. • The exam covers: – Internet Fundamentals – Web Page Authoring Fundamentals – Networking Fundamentals Defining the Internet Defining the Internet • The Internet is a worldwide connection of more than 171 million computers. • It uses the Internet Protocol (IP) to communicate. • Invented for the Advanced Research Projects Agency (ARPA) of the U.S. Department of Defense. • Used to create a decentralized network that could continue to function even if part of it was taken out by a nuclear bomb. Traffic on the Internet • Traffic volume is depicted by the lines. – Purple lines indicate 0 bytes – White lines indicate 100 billion bytes Who uses the Internet • People from all walks of life use the Internet. • The Internet is growing at a phenomen al rate. Identifying Eleven Popular Internet Services Internet Services The most popular services on the Net are: – – – – – – – – – – Electronic Mail (e-mail). Listserv Newsgroups Chat Videoconferencing File Transfer Protocol (FTP) Multimedia Streaming World Wide Web Rich Site Summary (RSS) Blogging Electronic Mail (e-mail) • Mails queue up in your mailbox. • Users read and respond at their convenience. Listserv • Listserv stands for List Server • It works like an electronic mailing list. • Users subscribe and then receive a copy of any e-mail sent to the list. • Electronic magazines (e-zines) are distributed using listservs. Newsgroups • Newgroups are an electronic bulletin-board service. • They contain discussions on any topic. • A newsreader is used to access a newsfeed. Chat • Real-time communications in chat rooms • Users type messages back and forth. Instant Messaging (IM) • Instant Messaging (IM) allows you to keep in contact with friends or associates. • When someone on your buddy list wants to talk to you, an instant message appears on your screen. Video Conferencing • Video conferencing uses a video camera and a microphone to allow people to see and hear each other. • Because of high bandwidth demands, it is not yet as popular as text-based messaging. FTP • File Transfer Protocol (FTP) is used to transfer files over the Internet from one computer to another. Multimedia Streaming • Streaming is the digital transmission of multimedia content in real time over the Internet. • Only the amount of data needed to continue playing is stored in a buffer in memory. • Many radio stations stream their programming live over the Internet. World Wide Web (WWW) • A hypertext system that allows documents to be shared over the Internet. – Hypertext refers to text that has been linked. Browsers • Mosaic is a graphical user interface that made the Internet extremely easy to use. – Web pages may display pictures. – Links to audio and video may be included. • Netscape Navigator was soon released and became the most popular Web browser. • Microsoft introduced Internet Explorer. W3C • W3C is the World Wide Web Consortium. – It coordinates the research and development of new standards and features for the Web. Rich Site Summary • Rich Site Summary (RSS) allows syndicating of a Web site in a form that can be registered with an RSS publisher. • Other sites can subscribe to the Web site to access the RSS feed from an RSS publisher. • Uses eXtensible Markup Language (XML). Blogging • Blog is short for Web log. – A Web-accessible log is written by someone who wants to chronicle activity related to a given topic (often personal). – It is essentially keeping your diary online. Describing the Infrastructure of the Internet Client-Server Computing • The Internet is made up of computers that send and receive information in a clientserver environment. – Servers send information. • Servers devoted to sending Web pages are called Web servers. – Clients receive information. • When you search the Web using a Web browser, your computer is a client. TCP/IP • Information is transmitted over the Internet in units called packets. • TCP and IP are two protocols required to send packets. • Transmission Control Protocol (TCP) is used to break large packets into smaller ones. • Internet Protocol (IP) handles the addressing and routing of packets. IP Addresses • IP uses IP addresses to identify computers. • Each packet contains the source and destination IP addresses. • IP addresses consist of four 8-bit bytes ranging from 0 to 255. • IP addresses are often expressed in dotted quad notation. – Example: 140.147.249.7 DNS • DNS stands for Domain Name System. • DNS allows you to use alphanumeric characters instead of numbers for IP addresses – making it easier to remember them. – For example, www.loc.gov can be used to reach the Library of Congress instead of remembering 140.147.249.7. FQDN • A complete DNS address is called a Fully Qualified Domain Name (FQDN). – FQDNs have the format hostname.registered-domain-name.top-level-domain. Top-Level Domains • Top-Level Domains (TLD) in the United States include: • In the rest of the world, TLDs are usually country codes. TLD Country Codes Domains • Domain refers to the network to which a computer is connected. • Host name refers to the computer itself. • A domain can be subdivided into subdomains. • Possible formats are: – hostname.registered-domain-name.second-leveldomain.top-level-domain – hostname.subdomain-name.registered-domainname.top-level-domain ICANN • ICANN stands for Internet Corporation for Assigned Names and Numbers. – Assigns domain names, IP addresses, protocol parameters, and port numbers. Intranet • An Intranet is a network that uses the TCP/IP protocols to provide private services within an organization. – It uses Internet technology within a private network. Extranet • Extranet refers to Internet resources that are beyond the reach of the public and require a logon name and password to access. Changing the World via the Internet Convergence • Convergence is the process of unification that digitalization causes by enabling all the world’s traditional ways of communicating to work over a common communications medium on the Internet. • Digital divide refers to barriers faced by the unconnected. Mergers and Alliances • Corporate mergers and alliances have occurred as a result of the Internet and the digitalization of communication. Telecommuting • Telecommuting is the act of working from home by using computers, dial-up modems, or broadband network connections, and fax machines to perform work that formerly required a person to travel physically to work. – A person who telecommutes is a teleworker. Business & Advertising • The Internet has become a utility for businesses to advertise and market their products. – Companies offer free services to entice people to visit their Web site more often. – Pop-under (appear under an opened Web page) and pop-up (appear on top of an opened Web page) advertises are very common. Online Shopping • Teleshopping is purchasing products online. – Fifty-seven percent of adults shopped online in 2001. Online Banking • Now, you can pay your bills online with online banking. • You can also invest your money and manage your portfolio online. Government Services • The Net makes government services more widely available. Politics Information Warfare • Information warfare is an electronic attack or invasion of computer networks. – The Department of Defense is prepared to disconnect its worldwide network from the Internet if necessary. Homeland Security • The USA Patriot Act gives wide latitude to the government in using Internet surveillance systems. – Terrorists use the Internet to hide secret messages. – The FBI uses a system called Carnivore to intercept suspicious e-mails. Electronic Publishing • Electronic book (eBook) technology allows publishers to sell books in electronic format. – eBooks are in a full text searchable format. Television & Entertainment • The Internet competes with television for people’s free time. • You can find TV listings on the Internet. • Interactive TV merges the Internet and television. – Play along with Wheel of Fortune or Jeopardy. – Vote for your choice on Judge Judy. Teaching and Learning • Computer-based learning strategies lead to faster and better learning. • Learning can be customized to the individual student. Tracing the History of the Internet Origin of the Internet • The Internet began when the Advanced Research Projects Agency (ARPA) of the Department of Defense (DoD) began a network called ARPANET in 1969. – DOD wanted a network that could survive a nuclear attack without stopping communication. Colleges and Universities • In the 1970s, colleges and universities connected to ARPANET using IP. – In 1983, the military part broke off and became MILNET. • In 1986, the National Science Foundation (NSF) began NSFNET to connect the nation’s five supercomputer centers. – In 1991, commercial entities were allowed to connect to NSFNET. Internet Backbone & DNS • In 1995, NSFNET reverted to research; the Internet backbone traffic began to be routed through network providers. • In 1998, the U.S. government turned over management of the domain name space from InterNIC to ICANN. Internet2 • Declining cost and explosive growth in using the Internet has spurred research into a faster network called Internet2. Looking Into the Future of the Internet Improving the Infrastructure • Multicast backbone (MBONE) is a network of computers on the Internet specifically designed for the transmission of simultaneous live video and audio broadcasts. Streaming Media • Streaming media network vendors bring uninterrupted audio and video streams to end users. – Streaming media is fed directly to edge servers located near local ISPs. Streaming Media Internet2 • Internet2 is a project to create a higherspeed Internet. – Utilizes high-speed connection points called gigapops. – Resource Reservation Protocol (RSVP) reserves bandwidth from workstation to host computer. – Internet Protocol version 6 (IPv6) allows users to assign priorities to certain traffic. – Multicast increases multimedia throughput. Wireless Communications • Wireless technologies no longer require a cable to connect to the Internet. – Motorola’s 200 Smartphone brings the Internet to the palm of your hand. Bluetooth • Bluetooth is an emerging standard for high-speed wireless communication. – It enables communication among mobile computers, telephones, handheld devices, and the Internet. Wi-Fi • Wi-FI is a trade name based on IEEE 802.11 specification for wireless local area networking. • Wi-Fi access points are called HotSpots, an area over which you can connect. • FreeSpots are locations that offer free wireless Internet access. – Examples: Hotels, coffee shops, restaurants, and airports IP Telephony • IP telephony merges the public switched telephone network (PSTN) with IP. – It converges voice, video, and data into one network using Voice-over IP (VoIP). – Microsoft’s Telephone Application Program Interface (TAPI) enables Windows users to use IP telephony. – IP telephone calls are much cheaper than normal long-distance calls. Personal Digital Assistants • Personal digital assistants (PDAs) are portable, handheld computers. • Windows CE – A compact module version of Microsoft Windows – Example: Toshiba’s PocketPC • Palm OS – Created by Palm, Inc. specifically for a small device Artificial Intelligence • Artificial Intelligence (AI) includes: – Voice recognition – Text-to-Speech conversion – Foreign language translation – Image recognition – Bots Voice Recognition • Voice recognition allows software to recognize your voice and respond. – Voice-controlled Web surfing, legal dictation, environmental control systems, and word processing. Text-to-Speech Conversion • Text-to-speech conversion allows you to hear conversations and see them. Foreign Languages • Foreign language translation can translate Web pages, e-mail, chat, and other documents between languages. Image Recognition • Image recognition software can compare images using a visual template. – Search for images based on visual properties. Bots • Bots, short for robots, are software applications programmed to act as intelligent agents that go out on the network to find or do things for you. Digital TV and Video • Digital televisions provide a highresolution display screen that can integrate computer data, Web pages, and television broadcasts. HDTV • High-Definition Television (HDTV) is based on: – MPEG digital video compression – Transmission in packets that permit any combination of video, audio, and data – Progressive scanning for computer interoperability up to 60 frames per second (fps) at 1920 × 1080 pixels – CD-quality digital surround sound using Dolby AC-3 audio technology MPEG Digital Video • The Motion Pictures Experts Group (MPEG) developed the MPEG standard. – Eliminates redundant data in images. – Uses delta-frame encoding to record only the changes from one frame to another. MSN TV • An MSN TV Internet receiver is a device that combines your telephone with the video signal on your TV or VCR. – See Web pages on your TV screen. – Sometimes called telecomputer. Ultimate TV • UltimateTV allows you to record your favorite shows without a VCR, pause live television, create your own TV program line-up, and instantly replay anything you see on TV. Digital Hubs • Your personal PC will become a digital hub that coordinates all of the electronic devices in your home. – Play music in other rooms from your PC. – Distribute video streams to receivers throughout your home. – Print digital camera photos without plugging anything. – Keep an eye on your home while you are away over the Internet. – Remote control all of your home appliances.