The Internet book: everything you need to know about computer networking and how the Internet works/
Douglas E. Comer
- 3rd ed.
- Upper Saddle River, NJ: Prentice Hall, c2000.
- xxvi, 351 p. : ill. ; 24 cm.
Includes index.
Chapter 1 The Internet Has Arrived The World Is Changing 1 Numbers Do Not Tell The Story 2 Learning About The Internet 3 Understanding The Big Picture 3 Terminology And Technology 4 Growth And Adaptability 4 The Impact Of The Internet 4 Organization Of The Book 4 A Personal Note 5 Chapter 2 Getting Started: Hands-On Experience Introduction 7 The Web: Sites And Pages 8 Web Browsers and Browsing 8 Using A Browser 8 Examples Of Web Sites And Services 9 Summary 11 PART I Introduction To Networking Chapter 3 Telephones Everywhere Introduction 15 A Communication Service 15 Selling Communication 15 Limited Access 16 High Cost 17 The Difficult Transition 17 Ubiquitous Access 18 Relevance To The Internet 19 Chapter 4 The World Was Once Analog Introduction 21 Sound, Vibrations, And Analog Recording 21 Analog Electronic Devices 22 Many Electronic Devices Are Analog 23 The First Analog Communication 23 Analog Is Simple But Inaccurate 23 Sending An Analog Signal Across A Wire 24 Digital Music 25 The Digital Revolution 25 Computers Are Digital 26 Digital Recording 26 Using Digital To Recreate Analog. 26 Why Digital Music? 28 Summary 28 Chapter 5 The Once And Future Digital Network Introduction 31 The World Was Once Digital 31 A Telegraph Is Digital 32 Morse Code 32 Letters And Digits In Morse Code 33 Users Did Not Encounter Morse Code 34 Virtually Instant Commumcation 34 Speed Is Relative 34 The Telephone Became Digital 35 Relevance To The Internet 35 Binary Encoding Of Data On The Internet 36 Why Use Two Symbols? 36 Summary 36 Chapter 6 Basic Communication Introduction 37 Communication Using Electricity 37 Signals On Wires 38 Information Coding 38 Modems Allow Two-Way Traffic 39 A Character Code For Digital Information 40 Detecting Errors 41 Summary 43
Chapter 7 The Locai Area Network Arrives Introduction 45 Motivation 45 Interchangeable Media 46 A Computer Consists Of Circuit Boards 46 Circuit Boards Plug Into A Computer 46 Connecting One Computer To Another 47 LAN Technologies 48 Connecting A Computer To A LAN 49 The Importance Of LAN Technology 50 Relationship To The Internet 51 PART II A Brief History Of The Internet Chapter 8 Internet: The Early Years Many Independent Networks 55 The Proliferation Of LANs 55 Facts About LANs 56 LANs Are Incompatible 57 Wide Area Technologies Exist 57 Few WANs, Many LANs 58 WANs and LANs Are Incompatible 58 The Desirability Of A Single Network 59 The Department Of Defense Had Multiple Networks 59 Connecting Disconnected Machines 60 The Internet Emerges 60 The ARPANET Backbone 60 Internet Software 61 The Name Is TCP/IP 61 The Shock Of An Open System 61 Open Systems Are Necessary 62 TCP/IP Documentation Is Online 63 The Military Adopts TCP/IP 64 Summary 64 A Personal Note 64 Chapters Two Decades Of Incredible Growth Introduction 67 Disseminating The Software 67 Meanwhile, Back In Computer Science 68 The Internet Meets UNIX 68 The U.S. Military Makes A Commitmmt 69 The Internet Doubles In Size In One Year 69 Every Computer Science Department 70 Graduate Students Volunteer Their Time 70 The lAB evolves 71 The IETF 12 Doubling Again In A Year 72 The Internet Improves Science 72 NSF Takes A Leadership Role 73 Target: All Of Science And Engineering 73 NSF's Approach 73 The NSFNET Backbone 74 The ANS Backbone 74 Exponential Growth 75 A Commercial Assessment 77 The End Of Growth 77 Chapter 10 The Global Internet Introduction 79 Early ARPA Networks 79 Electronic Mail Among Computers 79 BFTNET And FIDONET 80 Networks In Europe 80 EBONE: The Internet In Europe 82 Backbones And Internet Hierarchy 82 Internet On All Continents 83 The World Of Internet after 1998 84 A Personal Note 85 Chapter 11 A Global Information Infrastructure Introduction 87 Existing Infrastructure 87 Communication Infrastructure 88 The Internet Infrastructure 90 The Internet C^ers Diverse Information Services 90 TCP/IP Provides Communication Facilities 90 A Personal Note 91 PART III How The Internet Works Chapter 12 Packet Switching Introduction 95 Sharing Saves Money 95 Sharing Introduces Delays 95 Sharing Wires 96 Selectable Channels 96 Sharing By Taking Turns 97 Packet Switching Avoids Delays 98 Each Packet Must Be Labeled 98 Computers Have Addresses 98 Packets Are Not All The Same Size 99 Packet Transmission Seems Instantaneous 99 Sharing Is Automatic 99 Network Hardware. Handles Sharing 1(K) Many Devices Can Use Packet Switching 100 Relevance To The Internet 100 Summary 101 Chapter 13 internet: A Network Of Networks Introduction 103 Network Technologies Are Incompatible 103 Coping With Incompatibility 104 Two Fundamental Concepts 104 Using A Computer To Interconnect Networks 106 Interconnecting Computers Pass Packets 107 Interconnecting Computers Are Called Routers 107 Routers Are The Building Blocks Of The Internet 108 Routers Accommodate Multiple Types Of Networks 108 Routers Can Interconnect WANs And LANs 109 Interconnecting Networks Was Revolutionary 110 Summary 110 Chapter 14 ISPs And Network Connections Introduction 111 Internet Service Providers And Fees 111 Customer Connections Form The Last Mile 112 Leased Circuits Are Expensive 112 Most Individuals Choose Dial-up Access 113 The Important Concept Of Continuous Connectivity 113 Instantaneous Access Changes Use 114 Newer Technologies Offer Inexpensive Dedicated Access 115 Wireless Can Reach Everyone 117 A Personal Note 117 Chapter 15 IP: Software To Create A Virtual Network • Introduction 119 Protocol: An Agreement For Communication 119 Basic Functionality: The Internet Protocol 120 IP Software On Every Machine 120 Internet Packets Are Called Datagrams 120 The Illusion Of A Giant Network 121 The Reality Of Internal Structure 122 Datagrams Travel In Packets 123 Every Computer Is Assigned A Unique Address 123 Internet Addresses 124 An Odd IP Address Syntax 124 IP Addresses Are Not Random 124 An Example Trip Through The Internet 125 Summary 126 Chapter 16 TCP: Software For Reliable Communication Introduction 127 A Packet Switching System Can Be Overrun 127 TCP Helps IP Guarantee Delivery 129 TCP Provides A Connection Between Computer Programs 130 The Magic Of Recovering Lost Datagrams 130 TCP Retransmission Is Automatic 131 TCP And IP Work Together 131 Summary 132 Chapter 17 Clients + Servers s Distributed Computing Introduction 133 Large Computers Use Networks For Input And Output 133 Small Computers Use Networks To Interact 134 Distributed Computing On The Internet 134 A Single Paradigm Explains All Distributed Computing 135 Programs Are Clients Or Servers 136 A Server Must Always Run 137 Summary 137 Chapter 18 Names For Computers Introduction 139 People Prefer Names To Numbers 139 Naming A Computer Can Be Difficult Or Fun 140 Computer Names Must Be Unique 141 Suffixes On Computer Names 141 Names With Many Parts 142 Domain Names Outside The US 143 Translating A Name To An Equivalent IP Address 143 Domain Name System Works Like Directory Assistance 144 Computer Name Lookup Is Automatic 144 IP Addresses And Domain Names Are Unrelated 146 Summary 147 Chapter 19 Why The internet Works Weil Introduction 149 The Internet Works Well 149 IP Provides Flexibility 150 TCP Provides Reliability 151 TCP/IP Software Was Engineered For Efficiency 151 TCP/IP Research Emphasized Practical Results 152 The Formula For Success 152 Summary 153 PART IV Services Available On The Internet Chapter 20 Electronic Mall Introduction 157 Description Of Functionality 157 The Best Of All Worlds 158 Each User Has A Mailbox For E-mail 158 Sending An E-mail Message 158 Notification That E-mail has Arrived 158 Reading An E-mail Message 159 E-mail Messages Look Like Interoffice Memos 159 E-mail Software Fills In Header Information 160 How E-mail Works 161 Using E-mail From A Personal Computer 162 Mailbox Address Format 162 Abbreviations Make E-mail Friendly 163 Aliases Permit Arbitrary Abbreviations 163 Aliases Shared By All Users Of A Computer System 164 Sending To Multiple Recipients 164 Mailing List: An Alias for Multiple Recipients 165 Public Mailing Lists And Mail Exploders 165 E-mail To And From Non-Intemet Sites 166 Access To Services Via E-mail 167 Speed, Reliability, And Expectations 167 Impact And Significance Of Electronic Mail 168 Joining A Mailing List 169 Chapter 21 Bulletin Board Service (Network News) Introduction 171 Description Of Functionality 171 Many Bulletin Boards With Diverse Topics 172 Network News 173 Newsgroup Names 173 Obtaining Network News And The Software To Read Articles 174 How Network News Appears To A User 175 Checking For News Articles 175 Article Expiration 175 Reading Network News 176 Selecting Articles 176 s ,, Subscribing And Unsubscribing To Newsgroups 178 Submitting An Article 178 Moderated Newsgroups 178 Size Of Network News 179 How Network News Works 179 Redundant Newsfeeds And Duplicate Elimination 180 Relationship Between Netnews And Electronic Mail 181 Impact And Significance Of Network News And Mailing Lists 181 Hints And Conventions For Participating In Discussions 182 Summary 183 Chapter 22 Browsing The World Wide Web Introduction 185 Description Of Functionality 185 Browsing Vs. Information Retrieval 186 Early Browsing Services Used Menus 186 A Mqnu Item Can Point To Another Computer 187 How A Browser Works 187 An Example Point-And-Click Interface 188 Combining Menu Items With Text 189 The Importance Of Integrated Menus 191 Menus Embedded In Text Are Called Hypertext 191 Multimedia 193 Video And Audio References Can Be Embedded In Text 194 The World Wide Web 195 Browser Software Used To Access The Web 195 An Example Hypermedia Display 196 Control Of The Browser 198 External References 199 Recording The Location Of Information 199 Bookmarks 201 How The World Wide Web Works 202 A URL Tells A Browser Which Computer To Contact 202 A URL Tells A Browser Which Server To Contact 202 Use Of The Name WWW In URLs 203 A Browser Provides Access To Multiple Services 204 Inside A Browser Program 204 Summary 205 An Observation About Hypermedia Browsing 206 Chapter 23 World Wide Web Documents (HTML) Introduction 207 Display Hardware Varies 207 A Browser Translates And Displays A Web Document 208 A Consequence Of The Web Approach 208 HTML, The Language Used For Web Documents 209 Instructions In A Web Page Control The Output 210 A Web Page Is Divided Into Two Main Sections 210 Indentation Can Make HTML Readable 211 The Body Of A Web Page Can Contain Text 212 Indentation Can Make Paragraphs Easier To Find 213 A Web Page Can Link To Another Page 214 HTML Allows Numbered And Unnumbered Lists 215 Images On A Web Page Are Digital 216 HTML Allows A Web Page To Include An Image 217 Text Can Appear Adjacent To An Image 218 Images Can Link To Another Web Page 219 Some Browsers Can Stretch Or Shrink Images 220 The Background Can Be Controlled 220 Other Features Of HTML 220 Importance Of HTML 221 GUI Tools Help With Web Page Creation 221 Summary 222 Chapter 24 Advanced Web Technologies (Forms, Frames, Plugins, CGI, Java, JavaScript) Introduction 223 Conventional Web Pages Are Static 223 How A Server Stores Static Web Pages 224 Fetching Items One At A Time 226 Conventional Web Pages Use The Entire Screen 226 A Web Page Can Change Part Of the Screen Til The Web, Advertising, And Frames 229 Static Documents Have Disadvantages 230 XX O Controlling How A Browser Processes Data 230 Plugins Allow Variety 232 A Server Can Compute A Web Page On Demand 232 How CGI Works 233 Professional Programmers Build CGI Programs 235 Personalized Web Pages 235 Personalized Advertisements 236 Web Pages Can Interact 236 Shopping Carts 237 Cookies 237 Should You Accept Cookies? 238 A Web Page Can Display Single Animations 238 Active Documents Are More Powerful 239 Java Is An Active Document Technology 241 JavaScript Is An Active Document Technology 241 The Importance Of Advanced Web Technologies 242 Chapter 25 Automated Web Search (Search Engines) Introduction 243 Description Of Functionality 243 Browsing Vs. Automated Searching 244 A Search Engine Helps Users Get Started 244 A Search Tool Can Help Recover From Loss 245 Automated Searching By Name 245 How An Automated Search Service Operates 246 Modem Systems Search Web Page Contents 248 How A Web Search Appears To A User 248 How A Search Engine Returns Results 249 Automated Search Services Use String Matching 250 The Advantages And Disadvantages Of String Matching 251 Advanced Search Programs That Use Multiple Keys 252 Advanced Services Offer More Sophisticated Matching 252 Personalized Search Results 253 How An Automated Content Search Works 254 Searches Are Restricted 255 Advertising Pays For Searching 255 Examples OfAutomated Search Services 256 Significance Of Automated Web Search 256 Chapter 26 Audio And Video Communication Introduction 257 Description Of Functionality 257 Audio And Video Require Special Hardware 258 An Audio Clip Resembles An Audio CD 259 Real-Time Means No Delay 259 Internet Audio In Real-Time 259 Radio Programs On The Internet 260 Real-Time Transmission Is Called Webcasting 261 Internet Telephone Service Is Possible 261 Audio Teleconferencing 262 A Cooperative Document Markup Service 262 Marking A Document 264 The Participants Discuss And Mark A Document 265 Video Teleconferencing 266 Video Teleconference Among Groups Of People 267 A Combined Audio, Video, And Whiteboard Service 267 Summary 267 A Personal Note 268 Chapter 27 Faxes And Fiies (FTP) Introduction 269 Sending A Fax 269 The Internet Can Be Used To Copy Files 270 Data Stored In Files 270 Copying A File 271 FTP Is Interactive 271 Example FTP Commands 271 A User Can Store Or Retrieve A File 272 Commands For Binary And Text File Format 272 Choosing ASCII or Binary Transfer 273 Commands For Authorization And Anonymous FTP 273 A Browser Can Use FTP 21A ^ How FTP Works 21A Impact And Significance Of FTP 275 Summary 275 Chapter 28 Remote Login And Remote Desktops (TELNET) Introduction 277 Early Computers Used Textual Interfaces 211 A Timesharing System Requires User Identification 278 Remote Login Resembles Conventional Login 278 How Remote Login Works 279 Escaping From Remote Login 280 Displays And Windows 280 The Internet Remote Login Standard Is TELNET 280 Remote Access Can Display A Desktop 281 How Remote Desktops Operate 282 Assessment Of Remote Login And Desktops 282 Remote Access Is General 283 Generality Makes Remote Login And Desktops Powerful 283 Remote Access Accommodates Multiple Types Of Computers 283 Unexpected Results From Remote Access 284 Summary 284 Chapter 29 Facilities For Secure Communication Introduction 287 The Internet Is Unsecure 287 Lack Of Security Can Be Important 288 Authentication And Privacy Are Primary Problems 288 Data May Be Changed 289 Encoding Keeps Messages Private 289 Computer Encryption Uses Mathematics 289 No Network Is Absolutely Secure 290 Encryption Makes E-mail Private 290 Encryption Software Needs A Key 291 Two Keys Means Never Having To Trust Anyone 291 Secure E-Mail In Practice 293 Summary 293 Chapter 30 Electronic Commerce And Business Introduction 295 E-Commerce Is Big Business 295 Security Made E-Commerce Possible 296 Secure Sockets 296 Public Key Encryption Provides Authenticity 297 Digital Signatures 298 Certificates Contain Public Keys 298 What Is Digital Money? 299 Digital Cash Is Not Widely Available 299 Business And E-Commerce 300 A Business Must Protect Its Networks 300 Firewalls Protect Networks 300 A Firewall Filters Packets 301 Firewalls Guard Against Trojan Horses 301 Chapter 31 The Global Digital Library Introduction 303 A Cornucopia Of Services 303 New Services Appear Regularly 304 Flexibility Permits Change 304 A Digital Library 305 Card Catalogs And Search Tools 305 Internet Services Can Be Integrated 305 Mr. Dewey, Where Are You? 306 Information In The Digital Library 307 What Is The Internet? • 307 A Personal Note 301