Internet Book, The: Everything You Need to Know About Computer Networking and How the Internet Works

by Comer, Douglas E.

• ISBN13: 9780130308528
• ISBN10: 0130308528
• Edition: 3rd
• Format: Paperback
• Copyright: 2000-01-01
• Publisher: PRENTICE HALL

Summary

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. Doug Comer's, The Internet Book, Third Edition utilizes a non-technical perspective to explain the technology of how computers communicate, what the Internet is, how the Internet works, and what the Internet can do for people. This book works to fully connect students to the big picture by presenting a solid overview of networking and the Internet, rather than burying them with details. Comer assumes no prior background in computer networking or the Internet.

Table of Contents

Preface	xxv
The Internet Has Arrived	1	(6)
The World Is Changing	1	(1)
Numbers Do Not Tell The Story	2	(1)
Learning About The Internet	3	(1)
Understanding The Big Picture	3	(1)
Terminology And Technology	4	(1)
Growth And Adaptability	4	(1)
The Impact Of The Internet	4	(1)
Organization Of The Book	4	(1)
A Personal Note	5	(2)
Getting Started: Hands-On Experience	7	(8)
Introduction	7	(1)
The Web: Sites And Pages	8	(1)
Web Browsers and Browsing	8	(1)
Using A Browser	8	(1)
Examples Of Web Sites And Services	9	(2)
Summary	11	(4)
PART I Introduction To Networking
Telephones Everywhere	15	(6)
Introduction	15	(1)
A Communication Service	15	(1)
Selling Communication	15	(1)
Limited Access	16	(1)
High Cost	17	(1)
The Difficult Transition	17	(1)
Ubiquitous Access	18	(1)
Relevance To The Internet	19	(2)
The World Was Once Analog	21	(10)
Introduction	21	(1)
Sound, Vibrations, And Analog Recording	21	(1)
Analog Electronic Devices	22	(1)
Many Electronic Devices Are Analog	23	(1)
The First Analog Communication	23	(1)
Analog Is Simple But Inaccurate	23	(1)
Sending An Analog Signal Across A Wire	24	(1)
Digital Music	25	(1)
The Digital Revolution	25	(1)
Computers Are Digital	26	(1)
Digital Recording	26	(1)
Using Digital To Recreate Analog	26	(2)
Why Digital Music?	28	(1)
Summary	28	(3)
The Once And Future Digital Network	31	(6)
Introduction	31	(1)
The World Was Once Digital	31	(1)
A Telegraph Is Digital	32	(1)
Morse Code	32	(1)
Letters And Digits In Morse Code	33	(1)
Users Did Not Encounter Morse Code	34	(1)
Virtually Instant Communication	34	(1)
Speed Is Relative	34	(1)
The Telephone Became Digital	35	(1)
Relevance To The Internet	35	(1)
Binary Encoding Of Data On The Internet	36	(1)
Why Use Two Symbols?	36	(1)
Summary	36	(1)
Basic Communication	37	(8)
Introduction	37	(1)
Communication Using Electricity	37	(1)
Signals On Wires	38	(1)
Information Coding	38	(1)
Modems Allow Two-Way Traffic	39	(1)
A Character Code For Digital Information	40	(1)
Detecting Errors	41	(2)
Summary	43	(2)
The Local Area Network Arrives	45	(10)
Introduction	45	(1)
Motivation	45	(1)
Interchangeable Media	46	(1)
A Computer Consists Of Circuit Boards	46	(1)
Circuit Boards Plug Into A Computer	46	(1)
Connecting One Computer To Another	47	(1)
LAN Technologies	48	(1)
Connecting A Computer To A LAN	49	(1)
The Importance Of LAN Technology	50	(1)
Relationship To The Internet	51	(4)
PART II A Brief History Of The Internet
Internet: The Early Years	55	(12)
Many Independent Networks	55	(1)
The Proliferation Of LANs	55	(1)
Facts About LANs	56	(1)
LANs Are Incompatible	57	(1)
Wide Area Technologies Exist	57	(1)
Few WANs, Many LANs	58	(1)
WANs and LANs Are Incompatible	58	(1)
The Desirability Of A Single Network	59	(1)
The Department Of Defense Had Multiple Networks	59	(1)
Connecting Disconnected Machines	60	(1)
The Internet Emerges	60	(1)
The ARPANET Backbone	60	(1)
Internet Software	61	(1)
The Name Is TCP/IP	61	(1)
The Shock Of An Open System	61	(1)
Open Systems Are Necessary	62	(1)
TCP/IP Documentation Is Online	63	(1)
The Military Adopts TCP/IP	64	(1)
Summary	64	(1)
A Personal Note	64	(3)
Two Decades Of Incredible Growth	67	(12)
Introduction	67	(1)
Disseminating The Software	67	(1)
Meanwhile, Back In Computer Science	68	(1)
The Internet Meets UNIX	68	(1)
The U.S. Military Makes A Commitment	69	(1)
The Internet Doubles In Size In One Year	69	(1)
Every Computer Science Department	70	(1)
Graduate Students Volunteer Their Time	70	(1)
The IAB evolves	71	(1)
The IETF	72	(1)
Doubling Again In A Year	72	(1)
The Internet Improves Science	72	(1)
NSF Takes A Leadership Role	73	(1)
Target: All Of Science And Engineering	73	(1)
NSF's Approach	73	(1)
The NSFNET Backbone	74	(1)
The ANS Backbone	74	(1)
Exponential Growth	75	(2)
A Commercial Assessment	77	(1)
The End Of Growth	77	(2)
The Global Internet	79	(8)
Introduction	79	(1)
Early ARPA Networks	79	(1)
Electronic Mail Among Computers	79	(1)
BITNET And FIDONET	80	(1)
Networks In Europe	80	(2)
EBONE: The Internet In Europe	82	(1)
Backbones And Internet Hierarchy	82	(1)
Internet On All Continents	83	(1)
The World Of Internet after 1998	84	(1)
A Personal Note	85	(2)
A Global Information Infrastructure	87	(8)
Introduction	87	(1)
Existing Infrastructure	87	(1)
Communication Infrastructure	88	(2)
The Internet Infrastructure	90	(1)
The Internet Offers Diverse Information Services	90	(1)
TCP/IP Provides Communication Facilities	90	(1)
A Personal Note	91	(4)
PART III How The Internet Works
Packet Switching	95	(8)
Introduction	95	(1)
Sharing Saves Money	95	(1)
Sharing Introduces Delays	95	(1)
Sharing Wires	96	(1)
Selectable Channels	96	(1)
Sharing By Taking Turns	97	(1)
Packet Switching Avoids Delays	98	(1)
Each Packet Must Be Labeled	98	(1)
Computers Have Addresses	98	(1)
Packets Are Not All The Same Size	99	(1)
Packet Transmission Seems Instantaneous	99	(1)
Sharing Is Automatic	99	(1)
Network Hardware Handles Sharing	100	(1)
Many Devices Can Use Packet Switching	100	(1)
Relevance To The Internet	100	(1)
Summary	101	(2)
Internet: A Network Of Networks	103	(8)
Introduction	103	(1)
Network Technologies Are Incompatible	103	(1)
Coping With Incompatibility	104	(1)
Two Fundamental Concepts	104	(2)
Using A Computer To Interconnect Networks	106	(1)
Interconnectig Computers Pass Packets	107	(1)
Interconnecting Computers Are Called Routers	107	(1)
Routers Are The Building Blocks Of The Internet	108	(1)
Routers Accommodate Multiple Types Of Networks	108	(1)
Routers Can Interconnect WANs And LANs	109	(1)
Interconnecting Networks Was Revolutionary	110	(1)
Summary	110	(1)
ISPs And Network Connections	111	(8)
Introduction	111	(1)
Internet Service Providers And Fees	111	(1)
Customer Connections Form The Last Mile	112	(1)
Leased Circuits Are Expensive	112	(1)
Most Individuals Choose Dial-up Access	113	(1)
The Important Concept Of Continuous Connectivity	113	(1)
Instantaneous Access Changes Use	114	(1)
Newer Technologies Offer Inexpensive Dedicated Access	115	(2)
Wireless Can Reach Everyone	117	(1)
A Personal Note	117	(2)
IP: Software To Create A Virtual Network	119	(8)
Introduction	119	(1)
Protocol: An Agreement For Communication	119	(1)
Basic Functionality: The Internet Protocol	120	(1)
IP Software On Every Machine	120	(1)
Internet Packets Are Called Datagrams	120	(1)
The Illusion Of A Giant Network	121	(1)
The Reality Of Internal Structure	122	(1)
Datagrams Travel In Packets	123	(1)
Every Computer Is Assigned A Unique Address	123	(1)
Internet Addresses	124	(1)
An Odd IP Address Syntax	124	(1)
IP Addresses Are Not Random	124	(1)
An Example Trip Through The Internet	125	(1)
Summary	126	(1)
TCP: Software For Reliable Communication	127	(6)
Introduction	127	(1)
A Packet Switching System Can Be Overrun	127	(2)
TCP Helps IP Guarantee Delivery	129	(1)
TCP Provides A Connection Between Computer Programs	130	(1)
The Magic Of Recovering Lost Datagrams	130	(1)
TCP Retransmission Is Automatic	131	(1)
TCP And IP Work Together	131	(1)
Summary	132	(1)
Clients + Servers = Distributed Computing	133	(6)
Introduction	133	(1)
Large Computers Use Networks For Input And Output	133	(1)
Small Computers Use Networks To Interact	134	(1)
Distributed Computing On The Internet	134	(1)
A Single Paradigm Explains All Distributed Computing	135	(1)
Programs Are Clients Or Servers	136	(1)
A Server Must Always Run	137	(1)
Summary	137	(2)
Names For Computers	139	(10)
Introduction	139	(1)
People Prefer Names To Numbers	139	(1)
Naming A Computer Can Be Difficult Or Fun	140	(1)
Computer Names Must Be Unique	141	(1)
Suffixes On Computer Names	141	(1)
Names With Many Parts	142	(1)
Domain Names Outside The US	143	(1)
Translating A Name To An Equivalent IP Address	143	(1)
Domain Name System Works Like Directory Assistance	144	(1)
Computer Name Lookup Is Automatic	144	(2)
IP Addresses And Domain Names Are Unrelated	146	(1)
Summary	147	(2)
Why The Internet Works Well	149	(8)
Introduction	149	(1)
The Internet Works Well	149	(1)
IP Provides Flexibility	150	(1)
TCP Provides Reliability	151	(1)
TCP/IP Software Was Engineered For Efficiency	151	(1)
TCP/IP Research Emphasized Practical Results	152	(1)
The Formula For Success	152	(1)
Summary	153	(4)
PART IV Services Available On The Internet
Electronic Mail	157	(14)
Introduction	157	(1)
Description Of Functionality	157	(1)
The Best Of All Worlds	158	(1)
Each User Has A Mailbox For E-mail	158	(1)
Sending An E-mail Message	158	(1)
Notification That E-mail has Arrived	158	(1)
Reading An E-mail Message	159	(1)
E-mail Messages Look Like Interoffice Memos	159	(1)
E-mail Software Fills In Header Information	160	(1)
How E-mail Works	161	(1)
Using E-mail From A Personal Computer	162	(1)
Mailbox Address Format	162	(1)
Abbreviations Make E-mail Friendly	163	(1)
Aliases Permit Arbitrary Abbreviations	163	(1)
Aliases Shared By All Users Of A Computer System	164	(1)
Sending To Multiple Recipients	164	(1)
Mailing List: An Alias for Multiple Recipients	165	(1)
Public Mailing Lists And Mail Exploders	165	(1)
E-mail To And From Non-Internet Sites	166	(1)
Access To Services Via E-mail	167	(1)
Speed, Reliability, And Expectations	167	(1)
Impact And Significance Of Electronic Mail	168	(1)
Joining A Mailing List	169	(2)
Bulletin Board Service (Network News)	171	(14)
Introduction	171	(1)
Description Of Functionality	171	(1)
Many Bulletin Boards With Diverse Topics	172	(1)
Network News	173	(1)
Newsgroup Names	173	(1)
Obtaining Network News And The Software To Read Articles	174	(1)
How Network News Appears To A User	175	(1)
Checking For News Articles	175	(1)
Article Expiration	175	(1)
Reading Network News	176	(1)
Selecting Articles	176	(2)
Subscribing And Unsubscribing To Newsgroups	178	(1)
Submitting An Article	178	(1)
Moderated Newsgroups	178	(1)
Size Of Network News	179	(1)
How Network News Works	179	(1)
Redundant Newsfeeds And Duplicate Elimination	180	(1)
Relationship Between Netnews And Electronic Mail	181	(1)
Impact And Significance Of Network News And Mailing Lists	181	(1)
Hints And Conventions For Participating In Discussions	182	(1)
Summary	183	(2)
Browsing The World Wide Web	185	(22)
Introduction	185	(1)
Description Of Functionality	185	(1)
Browsing Vs. Information Retrieval	186	(1)
Early Browsing Services Used Menus	186	(1)
A Menu Item Can Point To Another Computer	187	(1)
How A Browser Works	187	(1)
An Example Point-And-Click Interface	188	(1)
Combining Menu Items With Text	189	(2)
The Importance Of Integrated Menus	191	(1)
Menus Embedded In Text Are Called Hypertext	191	(2)
Multimedia	193	(1)
Video And Audio References Can Be Embedded In Text	194	(1)
The World Wide Web	195	(1)
Browser Software Used To Access The Web	195	(1)
An Example Hypermedia Display	196	(2)
Control Of The Browser	198	(1)
External References	199	(1)
Recording The Location Of Information	199	(2)
Bookmarks	201	(1)
How The World Wide Web Works	202	(1)
A URL Tells A Browser Which Computer To Contact	202	(1)
A URL Tells A Browser Which Server To Contact	202	(1)
Use Of The Name WWW In URLs	203	(1)
A Browser Provides Access To Multiple Services	204	(1)
Inside A Browser Program	204	(1)
Summary	205	(1)
An Observation About Hypermedia Browsing	206	(1)
World Wide Web Documents (HTML)	207	(16)
Introduction	207	(1)
Display Hardware Varies	207	(1)
A Browser Translates And Displays A Web Document	208	(1)
A Consequence Of The Web Approach	208	(1)
HTML, The Language Used For Web Documents	209	(1)
Instructions In A Web Page Control The Output	210	(1)
A Web Page Is Divided Into Two Main Sections	210	(1)
Indentation Can Make HTML Readable	211	(1)
The Body Of A Web Page Can Contain Text	212	(1)
Indentation Can Make Paragraphs Easier To Find	213	(1)
A Web Page Can Link To Another Page	214	(1)
HTML Allows Numbered And Unnumbered Lists	215	(1)
Images On A Web Page Are Digital	216	(1)
HTML Allows A Web Page To Include An Image	217	(1)
Text Can Appear Adjacent To An Image	218	(1)
Images Can Link To Another Web Page	219	(1)
Some Browsers Can Stretch Or Shrink Images	220	(1)
The Background Can Be Controlled	220	(1)
Other Features Of HTML	220	(1)
Importance Of HTML	221	(1)
GUI Tools Help With Web Page Creation	221	(1)
Summary	222	(1)
Advanced Web Technologies (Forms, Frames, Plugins, CGI, Java, JavaScript)	223	(20)
Introduction	223	(1)
Conventional Web Pages Are Static	223	(1)
How A Server Stores Static Web Pages	224	(2)
Fetching Items One At A Time	226	(1)
Conventional Web Pages Use The Entire Screen	226	(1)
A Web Page Can Change Part Of the Screen	227	(2)
The Web, Advertising, And Frames	229	(1)
Static Documents Have Disadvantages	230	(1)
Controlling How A Browser Processes Data	230	(2)
Plugins Allow Variety	232	(1)
A Server Can Compute A Web Page On Demand	232	(1)
How CGI Works	233	(2)
Professional Programmers Build CGI Programs	235	(1)
Personalized Web Pages	235	(1)
Personalized Advertisements	236	(1)
Web Pages Can Interact	236	(1)
Shopping Carts	237	(1)
Cookies	237	(1)
Should You Accept Cookies?	238	(1)
A Web Page Can Display Simple Animations	238	(1)
Active Documents Are More Powerful	239	(2)
Java Is An Active Document Technology	241	(1)
JavaScript Is An Active Document Technology	241	(1)
The Importance Of Advanced Web Technologies	242	(1)
Automated Web Search (Search Engines)	243	(14)
Introduction	243	(1)
Description Of Functionality	243	(1)
Browsing Vs. Automated Searching	244	(1)
A Search Engine Helps Users Get Started	244	(1)
A Search Tool Can Help Recover From Loss	245	(1)
Automated Searching By Name	245	(1)
How An Automated Search Service Operates	246	(2)
Modern Systems Search Web Page Contens	248	(1)
How A Web Search Appears To A User	248	(1)
How A Search Engine Returns Results	249	(1)
Automated Search Services Use String Matching	250	(1)
The Advantages And Disadvantages Of String Matching	251	(1)
Advanced Search Programs That Use Multiple Keys	252	(1)
Advanced Services Offer More Sophisticated Matching	252	(1)
Personalized Search Results	253	(1)
How An Automated Content Search Works	254	(1)
Searches Are Restricted	255	(1)
Advertising Pays For Searching	255	(1)
Examples Of Automated Search Services	256	(1)
Significance Of Automated Web Search	256	(1)
Audio And Video Communication	257	(12)
Introduction	257	(1)
Description Of Functionality	257	(1)
Audio And Video Require Special Hardware	258	(1)
An Audio Clip Resembles An Audio CD	259	(1)
Real-Time Means No Delay	259	(1)
Internet Audio In Real-Time	259	(1)
Radio Programs On The Internet	260	(1)
Real-Time Transmission Is Called Webcasting	261	(1)
Internet Telephone Service Is Possible	261	(1)
Audio Teleconferencing	262	(1)
A Cooperative Document Markup Service	262	(2)
Marking A Document	264	(1)
The Participants Discuss And Mark A Document	265	(1)
Video Teleconferencing	266	(1)
Video Teleconference Among Groups Of People	267	(1)
A Combined Audio, Video, And Whiteboard Service	267	(1)
Summary	267	(1)
A Personal Note	268	(1)
Faxes And Files (FTP)	269	(8)
Introduction	269	(1)
Sending A Fax	269	(1)
The Internet Can Be Used To Copy Files	270	(1)
Data Stored In Files	270	(1)
Copying A File	271	(1)
FTP Is Interactive	271	(1)
Example FTP Commands	271	(1)
A User Can Store Or Retrieve A File	272	(1)
Commands For Binary And Text File Format	272	(1)
Choosing ASCII or Binary Transfer	273	(1)
Commands For Authorization And Anonymous FTP	273	(1)
A Browser Can Use FTP	274	(1)
How FTP Works	274	(1)
Impact And Significance Of FTP	275	(1)
Summary	275	(2)
Remote Login And Remote Desktops (TELNET)	277	(10)
Introduction	277	(1)
Early Computers Used Textual Interfaces	277	(1)
A Timesharing System Requires User Identification	278	(1)
Remote Login Resembles Conventional Login	278	(1)
How Remote Login Works	279	(1)
Escaping From Remote Login	280	(1)
Displays And Windows	280	(1)
The Internet Remote Login Standard Is TELNET	280	(1)
Remote Access Can Display A Desktop	281	(1)
How Remote Desktops Operate	282	(1)
Assessment Of Remote Login And Desktops	282	(1)
Remote Access Is General	283	(1)
Generality Makes Remote Login And Desktops Powerful	283	(1)
Remote Access Accommodates Multiple Types Of Computers	283	(1)
Unexpected Results From Remote Access	284	(1)
Summary	284	(3)
Facilities For Secure Communication	287	(8)
Introduction	287	(1)
The Internet Is Unsecure	287	(1)
Lack Of Security Can Be Important	288	(1)
Authentication And Privacy Are Primary Problems	288	(1)
Data May Be Changed	289	(1)
Encoding Keeps Messages Private	289	(1)
Computer Encryption Uses Mathematics	289	(1)
No Network Is Absolutely Secure	290	(1)
Encryption Makes E-mail Private	290	(1)
Encryption Software Needs A Key	291	(1)
Two Keys Means Never Having To Trust Anyone	291	(2)
Secure E-Mail In Practice	293	(1)
Summary	293	(2)
Electronic Commerce And Business	295	(8)
Introduction	295	(1)
E-Commerce Is Big Business	295	(1)
Security Made E-Commerce Possible	296	(1)
Secure Sockets	296	(1)
Public Key Encryption Provides Authenticity	297	(1)
Digital Signatures	298	(1)
Certificates Contain Public Keys	298	(1)
What Is Digital Money?	299	(1)
Digital Cash Is Not Widely Available	299	(1)
Business And E-Commerce	300	(1)
A Business Must Protect Its Networks	300	(1)
Firewalls Protect Networks	300	(1)
A Firewall Filters Packets	301	(1)
Firewalls Guard Against Trojan Horses	301	(2)
The Global Digital Library	303	(6)
Introduction	303	(1)
A Cornucopia Of Services	303	(1)
New Services Appear Regularly	304	(1)
Flexibility Permits Change	304	(1)
A Digital Library	305	(1)
Card Catalogs And Search Tools	305	(1)
Internet Services Can Be Integrated	305	(1)
Mr. Dewey, Where Are You?	306	(1)
Information In The Digital Library	307	(1)
What Is The Internet?	307	(1)
A Personal Note	307	(2)
Appendix 1 Example Netnews Newsgroups	309	(10)
Appendix 2 Glossary Of Internet Terms	319	(26)
Index	345

Excerpts

Preface The Internet Bookexplains how computers communicate, what the Internet is, how the Internet works, and what services the Internet offers you. It is designed for readers who do not have a strong technical background -- early chapters clearly explain the terminology and concepts needed to understand all the services. When you finish reading, you will understand the technology behind the Internet, will appreciate how the Internet can be used, and discover why people find it so exciting. In addition, you will understand the origins of the Internet and see how rapidly it has grown.Instead of using mathematics, algorithms, or computer programs, the book uses analogies from everyday life to explain technology. For example, to explain why digital communication is superior to analog, the text uses an analogy of sending signals through fog with a flashlight. To explain how audio can be played back for the user at a steady rate when packets arrive in clumps, the text uses the analogy of many gallons of milk arriving at a supermarket in one shipment, but being sold one gallon at a time.In addition to explaining the services users encounter such as e-mail, file transfer, and web browsing, the text covers key networking concepts such as packet switching, Local Area Networks, protocol software, and domain names. More important, the text builds on fundamentals -- it describes basic Internet communication facilities first, and then shows how the basic facilities are used to provide a variety of services. Finally, the book includes an extensive glossary of technical terms with easy-to-understand definitions; readers are encouraged to consult the glossary as they read.The third edition retains the same general structure as the previous edition, but adds four new chapters and updates material throughout. Chapter 2 surveys a variety of Web sites, and encourages readers to begin exploring the Web while they read. The other three new chapters are especially significant. Chapter 14 covers Internet connection technologies, including ADSL and cable modems, technologies which are now available to consumers. Chapters 29 and 30 cover the related topics of security and ecommerce, both of which are increasingly important. Chapter 29 explains encryption technology, and Chapter 30 shows how the technology is used to conduct business.As with the previous edition, the book is divided into four main parts. The first part begins with fundamental concepts such as digital and analog communication. It also introduces packet switching, and explains the Local Area Network technologies that are used in most businesses.The second part of the book gives a short history of the Internet research project and the development of the Internet. Although most of the history can be skipped, readers should pay attention to the phenomenal growth rate, which demonstrates that the technology was designed incredibly well -- no other communication technology has remained as unchanged through such rapid growth.The third part of the book explains how the Internet works, including a description of the two fundamental protocols used by all services: the Internet Protocol (IP) and the Transmission Control Protocol (TCP). Although they omit technical details, the chapters in this part allow students to understand the essential role of each protocol and gain perspective on the overall design.The fourth part of the book examines services available on the Internet. In addition to covering browsers, plugins, CGI, and search engines used with the World Wide Web, chapters discuss e-mail, network newsgroups, file and fax transfer, and audio and video communication. In each case, the text explains how the service operates and how it uses facilities in the underlying system.The Internet Bookmakes an excellent reference text for a college-level course on the Internet. Although presented in a nontechnical manner, the mater