For use as a primary text for courses on using the Internet, or as a supplement for computer literacy courses that cover networking or the Internet. Fully revised and updated throughout, this text explains – in non-technical language – the technology of how computers communicate, what the Internet is, how the Internet works, and what the Internet can do for people. Students connect to the material through Comer’s solid overview that focuses on the “big picture,” rather than the minute details. No background in computer networking or the Internet is assumed.

Table of Contents:
PART I Introduction To Networking   Chapter 1 The Internet Has Arrived The World Has Changed Numbers Do Not Tell The Story Learning About The Internet Understanding The Big Picture Terminology And Technology Growth And Adaptability The Impact Of The Internet Organization Of The Book A Personal Note   Chapter 2 Getting Started: Hands-On Experience Introduction The Web: Sites And Pages Web Browsers and Browsing Using A Browser Examples Of Web Sites And Services Internet Search Summary   Chapter 3 Telephones Everywhere Introduction A Communication Service Selling Communication Limited Access High Cost The Difficult Transition Ubiquitous Access Relevance To The Internet   Chapter 4 The World Was Once Analog Introduction Sound, Vibrations, And Analog Recording Analog Electronic Devices Many Electronic Devices Are Analog The First Analog Communication Analog Is Simple But Inaccurate Sending An Analog Signal Across A Wire Digital Music The Digital Revolution Computers Are Digital Digital Recording Using Digital To Recreate Analog Why Digital Music? Summary   Chapter 5 The Once And Future Digital Network Introduction The World Was Previously Digital A Telegraph Is Digital Morse Code Letters And Digits In Morse Code Users Did Not Encounter Morse Code Virtually Instant Communication Speed Is Relative The Telephone Became Digital Relevance To The Internet Binary Encoding Of Data On The Internet Why Use Two Symbols? Summary   Chapter 6 Basic Communication Introduction Communication Using Electricity Signals On Wires Information Coding Modems Allow Two-Way Traffic A Character Code For Digital Information Detecting Errors Summary   Chapter 7 The Local Area Network Arrives Introduction Motivation Interchangeable Media A Computer Consists Of Circuit Boards Circuit Boards Plug Into A Computer Connecting One Computer To Another LAN Technologies Connecting A Computer To A LAN The Importance Of LAN Technology Relationship To The Internet   PART II A Brief History Of The Internet   Chapter 8 Internet: The Early Years Many Independent Networks The Proliferation Of LANs Facts About LANs LANs Are Incompatible Wide Area Technologies Exist Few WANs, Many LANs WANs and LANs Are Incompatible The Desirability Of A Single Network The Department Of Defense Had Multiple Networks Connecting Disconnected Machines The Internet Emerges The ARPANET Backbone Internet Software The Name Is TCP/IP The Shock Of An Open System Open Systems Are Necessary TCP/IP Documentation Is Online The Military Adopts TCP/IP Summary A Personal Note   Chapter 9 Two Decades Of Incredible Growth Introduction Disseminating The Software Meanwhile, Back In Computer Science The Internet Meets UNIX The U.S. Military Makes A Commitment The Internet Doubles In Size In One Year Every Computer Science Department Graduate Students Volunteer Their Time The IAB evolves The IETF Doubling Again In A Year The Internet Improves Science NSF Takes A Leadership Role Target: All Of Science And Engineering NSF’s Approach The NSFNET Backbone The ANS Backbone Exponential Growth A Commercial Assessment The End Of Growth   Chapter 10 The Global Internet Introduction Early ARPA Networks Electronic Mail Among Computers BITNET And FIDONET Networks In Europe EBONE: The Internet In Europe Backbones And Internet Hierarchy Internet On All Continents The World Of Internet after 1998 A Personal Note   Chapter 11 A Global Information Infrastructure Introduction Existing Infrastructure Communication Infrastructure The Internet Infrastructure The Internet Offers Diverse Information Services TCP/IP Provides Communication Facilities A Personal Note   PART III How The Internet Works   Chapter 12 Packet Switching Introduction Sharing Saves Money Sharing Introduces Delays Sharing Wires Selectable Channels Sharing By Taking Turns Packet Switching Avoids Delays Each Packet Must Be Labeled Computers Have Addresses Packets Are Not All The Same Size Packet Transmission Seems Instantaneous Sharing Is Automatic Network Hardware Handles Sharing Many Devices Can Use Packet Switching Relevance To The Internet Summary   Chapter 13 Internet: A Network Of Networks Introduction Network Technologies Are Incompatible Coping With Incompatibility Two Fundamental Concepts Using A Computer To Interconnect Networks Interconnecting Computers Pass Packets Interconnecting Computers Are Called Routers Routers Are The Building Blocks Of The Internet The Internet Includes Multiple Types Of Networks Routers Can Interconnect WANs And LANs The Hierarchical Structure Of The Internet Where Packets Travel Interconnecting Networks Was Revolutionary Summary   Chapter 14 ISPs: Broadband And Wireless Access Introduction Internet Service Providers And Fees Customer Connections Form The Last Mile Leased Circuits Are Expensive Dial-up Access Is Inexpensive, But Slow Broadband Connections Offer High Speed The Important Concept Of Continuous Connectivity Instantaneous Access Changes Use Modern Technologies Offer Inexpensive Dedicated Access Wireless Access Is Available Wi-Fi And 3G Wireless Technologies A Personal Note   Chapter 15 IP: Software To Create A Virtual Network Introduction Protocol: An Agreement For Communication Basic Functionality: The Internet Protocol IP Software On Every Machine Internet Packets Are Called Datagrams The Illusion Of A Giant Network The Internet’s Internal Structure Datagrams Travel In Packets Every Computer Is Assigned A Unique Address Internet Addresses An Odd IP Address Syntax IP Addresses Are Not Random A Trip Through An Example Internet How Fast Is Your Connection? Summary   Chapter 16 TCP: Software For Reliable Communication Introduction A Packet Switching System Can Be Overrun TCP Helps IP Guarantee Delivery TCP Provides A Connection Between Computer Programs The Magic Of Recovering Lost Datagrams TCP Retransmission Is Automatic TCP And IP Work Together Summary   Chapter 17 Clients + Servers = Distributed Computing Introduction Large Computers Use Networks For Input And Output Small Computers Use Networks To Interact Distributed Computing On The Internet A Single Paradigm Explains All Distributed Computing Communicating Programs Are Clients Or Servers A Server Must Always Run Summary   Chapter 18 Names For Computers Introduction People Prefer Names To Numbers Naming A Computer Can Be Challenging Or Fun Computer Names Must Be Unique Suffixes On Computer Names Names With Many Parts Domain Names Outside The US Translating A Name To An Equivalent IP Address Domain Name System Works Like Directory Assistance Computer Name Lookup Is Automatic IP Addresses And Domain Names Are Unrelated Summary   Chapter 19 NAT: Sharing An Internet Connection Introduction High Capacity And Multiple Computers It Is Possible To Share A Single IP Address A Device For Connection Sharing Is Called A NAT Box A NAT Box Acts Like A Miniature ISP NAT Changes The Address In Each Datagram Computer Software Can Perform The NAT Function NAT Can Use A Wireless Network Summary   Chapter 20 Why The Internet Works Well Introduction The Internet Works Well IP Provides Flexibility TCP Provides Reliability TCP/IP Software Was Engineered For Efficiency TCP/IP Research Emphasized Practical Results The Formula For Success Summary   PART IV Services Available On The Internet   Chapter 21 Electronic Mail Introduction Description Of Functionality The Best Of All Worlds Each User Has A Mailbox For Email Sending An Email Message Notification That Email Has Arrived Reading An Email Message A Browser Can Be Used To Send And Receive Email Email Messages Look Like Interoffice Memos Email Software Fills In Header Information How Email Works Using Email From A Personal Computer Mailbox Address Format Abbreviations Make Email Friendly Aliases Permit Arbitrary Abbreviations Aliases Shared By All Users Of A Computer System Sending To Multiple Recipients Mailing List: An Alias for Multiple Recipients Public Mailing Lists And Mail Exploders Exchanging Email With Non-Internet Sites Access To Services Via Email Speed, Reliability, And Expectations Impact And Significance Of Electronic Mail A Convention For Joining A Mailing List   Chapter 22 Bulletin Board Service (Newsgroups) Introduction Description Of Functionality Many Bulletin Boards With Diverse Topics Network News Categories Obtaining Network News And The Software To Read Articles How Network News Appears To A User Checking For News Articles Reading Network News Submission Of An Article Moderated Newsgroups Size Of Network News Impact And Significance Of Newsgroups And Mailing Lists Hints And Conventions For Participating In Discussions Summary   Chapter 23 Browsing The World Wide Web Introduction Description Of Functionality Browsing Vs. Information Retrieval Early Browsing Services Used Menus A Menu Item Can Point To Another Computer How A Browser Works An Example Point-And-Click Interface Combining Menu Items With Text The Importance Of Integrated Links Embedded Links In Text Are Called Hypertext Multimedia Video And Audio References Can Be Embedded In Text The World Wide Web Browser Software Used To Access The Web An Example Hypermedia Display Control Of A Browser External References Recording The Location Of Information Bookmarks Or Favorites How The World Wide Web Works A URL Tells A Browser Which Computer To Contact A URL Tells A Browser Which Server To Contact Use Of The Name www In URLs A Browser Provides Access To Multiple Services Inside A Browser Program Summary An Observation About Hypermedia Browsing   Chapter 24 World Wide Web Documents (HTML) Introduction Display Hardware Varies A Browser Translates And Displays A Web Document A Consequence Of The Web Approach HTML, The Language Used For Web Documents Instructions In A Web Page Control The Output A Web Page Is Divided Into Two Main Sections Indentation Can Make HTML Readable The Body Of A Web Page Can Contain Text Indentation Can Make Paragraphs Easier To Find A Web Page Can Link To Another Page HTML Allows Numbered And Unnumbered Lists Images On A Web Page Are Digital HTML Allows A Web Page To Include An Image Text Can Appear Adjacent To An Image Images Can Link To Another Web Page Some Browsers Can Stretch Or Shrink Images The Background Can Be Controlled Other Features Of HTML Importance Of HTML GUI Tools Help With Web Page Creation Summary   Chapter 25 Advanced Web Technologies (Forms, Frames, Plugins, Java, JavaScript, Flash) Introduction Conventional Web Pages Are Static How A Server Stores Static Web Pages Fetching Items One At A Time Conventional Web Pages Use The Entire Screen A Web Page Can Change Part Of the Screen The Web, Advertising, And Frames Pop-Ups And Pop-Up Blockers Static Documents Have Disadvantages Controlling How A Browser Processes Data Plugins Allow Variety A Server Can Compute A Web Page On Demand How Server-Side Scripting Works Professional Programmers Build Server Scripts Personalized Web Pages Personalized Advertisements Web Pages Can Interact Shopping Carts Cookies Should You Accept Cookies? A Web Page Can Display Simple Animations Active Documents Are More Powerful Java Is An Active Document Technology JavaScript Is An Active Document Technology Flash And Real Technologies The Importance Of Advanced Web Technologies   Chapter 26 Group And Personal Web Pages (Wikis And Blogs) Introduction The Disadvantage Of A Bulletin Board System Shared Pages Shared Pages Are Called Wikis Sharing And Consensus Building The Disadvantage Of Wikis Wikipedia Is An Experiment Should You Trust Wikipedia? Publication Of A Personal Diary A Personal Note   Chapter 27 Automated Web Search (Search Engines) Introduction Description Of Functionality Browsing Vs. Automated Searching A Search Engine Helps Users Get Started A Search Tool Can Help Recover From Loss How An Automated Search Service Operates Gathering Information In Advance Modern Systems Search Web Page Contents How A Web Search Appears To A User How A Search Engine Returns Results Automated Search Services Use String Matching The Advantages And Disadvantages Of String Matching Automated Search Programs That Use Multiple Keys Advanced Services Offer More Sophisticated Matching Personalized Search Results More Details About How Content Searching Works Searches Are Restricted Advertising Pays For Searching Examples Of Automated Search Services Significance Of Automated Web Search   Chapter 28 Text, Audio, And Video Communication (IM, VoIP) Introduction Instant Messaging Provides Textual Communication Audio And Video Functionality Audio And Video Require Special Facilities An Audio Clip Resembles An Audio CD Real-Time Means No Delay Internet Audio In Real-Time Radio Programs On The Internet Real-Time Audio Transmission Is Called Webcasting Internet Telephone Service Is Possible Internet Telephone Service Is Known As VoIP Audio Teleconferencing A Cooperative Document Markup Service Marking A Document The Participants Discuss And Mark A Document Video Teleconferencing Video Teleconference Among Groups Of People A Combined Audio, Video, Whiteboard, And IM Service Summary A Personal Note   Chapter 29 Faxes, File Transfer, And File Sharing (FTP) Introduction Sending A Fax The Internet Can Be Used To Copy Files Data Stored In Files Copying A File FTP Is Invoked From A Browser FTP Allows A User To View Directory Contents FTP Allows A User To Upload Files FTP Transfers Must Be Authorized How FTP Works Impact And Significance Of FTP Peer-To-Peer File Sharing Summary   Chapter 30 Remote Login And Remote Desktops (TELNET) Introduction Early Computers Used Textual Interfaces A Timesharing System Requires User Identification Remote Login Resembles Conventional Login How Remote Login Works Escaping From Remote Login The Internet Remote Login Standard Is TELNET Remote Access Can Display A Desktop How Remote Desktops Operate Assessment Of Remote Login And Desktops Generality Makes Remote Login And Desktops Powerful Remote Access Accommodates Multiple Types Of Computers Unexpected Results From Remote Access Summary   Chapter 31 Facilities For Secure Communication Introduction The Internet Is Unsecure Lack Of Security Can Be Important Authentication And Privacy Are Primary Problems Data Can Be Changed Encoding Keeps Messages Private Computer Encryption Uses Mathematics No Network Is Absolutely Secure Encryption Makes Email Private Encryption Software Needs A Key Two Keys Means Never Having To Trust Anyone Secure Email In Practice Secure Wireless Networks Firewalls Protect Networks From Unwanted Packets A Firewall Filters Packets Firewalls Guard Against Trojan Horses Residential And Individual Firewalls Systems Exist To Detect Intrusion Service Can Be Denied Summary   Chapter 32 Secure Access From A Distance (VPNs) Introduction Organizations Grant Employees Special Privileges Traveling Employees Lose Privilege Telecommuters Do Not Have Privilege Dedicated Leased Circuits Allow Secure Telecommuting Standard Internet Connections Are Low-Cost Can A Technology Combine Advantages? A Virtual Private Network Solves The Problem How A VPN Works The Illusion Of A Direct Connection Significance Of VPNs   Chapter 33 Internet Economics And Electronic Commerce Introduction Who Pays For The Internet? E-commerce Is Big Business Security Technology Made E-commerce Possible Secure Sockets Public Key Encryption Provides Authenticity Digital Signatures Certificates Contain Public Keys What Is Digital Money? Digital Cash Is Not Widely Available Business And E-commerce   Chapter 34 The Global Digital Library Introduction A Cornucopia Of Services New Services Appear Regularly Flexibility Permits Change A Digital Library Card Catalogs And Search Tools Internet Services Can Be Integrated Mr. Dewey, Where Are You? Information In The Digital Library What Is The Internet?