Chapter 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 Acess
High Cost
The Difficult Transition
Ubiquitous Acess
Relevance To The Internet
Chapter 4 The World Was Once Analog
Introduction
Sound, Vibrations, And Analog Recording
Analog Electroni Devices
Many Electroni Devices Are Analog
The First Analog Communication
Analog Is Simple But Inacurate
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 En oding Of Data On The Internet
Why Use Two Symbols?
Summary
Chapter 6 BasicCommunication
Introduction
Communication Using Electricity
Signals On Wires
Information Coding
Modems Allow Two-Way Traffi
A Chara ter Code For Digital Information
Detecting Errors
Summary
Chapter 7 The Local Area Network Arrives
Introduction
Motivation
Inter hangeable Media
A Computer Consists Of Cir uit 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 Growthc
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 Netwos
Electroni Mail Amng Computers
BITNET And FIDONET
Networks In Europe
EBONE: The Internet In Europe
Ba kbones 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 Pa ket Switching
Introduction
Sharing Saves Money
Sharing Introduces Delays
Sharing Wires
Sele table 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 Automati
Network Hardware Handles Sharing
Many Devices Can Use Packet Switching
Relevan e To The Internet
Summary
Chapter 13 Internet: A Network Of Networks
Introdu tion
Network Te hnologies Are In ompatible
Coping With In ompatibility
Two Fundamental Con epts
Using A Computer To Inter onne t Networks
Inter onne ting Computers Pass Pa kets
Inter onne ting Computers Are Called Routers
Routers Are The Building Blo ks Of The Internet
The Internet In ludes Multiple Types Of Networks
Routers Can Inter onne t WANs And LANs
The Hierar hi al Stru ture Of The Internet
Where Pa kets Travel
Inter onne ting Networks Was Revolutionary
Summary
Chapter 14 ISPs: Broadband And Wireless A ess
Introdu tion
Internet Servi e Providers And Fees
Customer Conne tions Form The Last Mile
Leased Cir uits Are Expensive
Dial-up A ess Is Inexpensive, But Slow
Broadband Conne tions Offer High Speed
The Important Con ept Of Continuous Conne tivity
Instantaneous A ess Changes Use
Modern Te hnologies Offer Inexpensive Dedi ated A ess
Wireless A ess Is Available
Wi-Fi And 3G Wireless Te hnologies
A Personal Note
Chapter 15 IP: Software To Create A Virtual Network
Introduction
Protocol: An Agreement For Communication
Basi 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 Pa kets
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 Magi Of Recovering Lost Datagrams
TCP Retransmission Is Automati
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 Automati
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 Conne tion Sharing Is Called A NAT Box ..
A NAT Box A ts 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
Introdu tion
The Internet Works Well
IP Provides Flexibility
TCP Provides Reliability
TCP/IP Software Was Engineered For Effi ien y
TCP/IP Research Emphasized Practical Results
The Formula For Sucess
Summary
PART IV Servi es Available On The Internet
Chapter 21 Ele troni Mail
Introdu tion
Des ription Of Fun tionality
The Best Of All Worlds
Ea h User Has A Mailbox For Email
Sending An Email Message
Notifi ation That Email Has Arrived
Reading An Email Message
A Browser Can Be Used To Send And Re eive Email
Email Messages Look Like Interoffi e 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
Publi Mailing Lists And Mail Exploders
Ex hanging Email With Non-Internet Sites
Acess To Services Via Email
Speed, Reliability, And Expectations
Impact And Significance Of Electroni 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 Acess 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 Acess 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
Instru tions 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
Importan e Of HTML
GUI Tools Help With Web Page Creation
Summary
Chapter 25 Advanced Web Technologies (Forms, Frames, Plugins, Java, JavaS ript, Flash)
Introdu tion
Conventional Web Pages Are Stati
How A Server Stores Stati 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
Stati Do uments 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 Acept Cookies?
A Web Page Can Display Simple Animations
Active Documents Are More Powerful
Java Is An Active Document Technology
JavaScript Is An Active Do ument Te hnology
Flash And Real Te hnologies
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)
Introdu tion
Description Of Functionality
Browsing Vs. Automated Searching
A Search Engine Helps Users Get Started
A Search Tool Can Help Re over 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 Tele onferencing
A Cooperative Document Markup Service
Marking A Document
The Participants Discuss And Mark A Document
Video Tele onferencing
Video Tele onference 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)
Introdu tion
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)
Introdu tion
Early Computers Used Textual Interfaces
A Timesharing System Requires User Identification
Remote Login Resembles Conventional Login
How Remote Login Works
Es aping From Remote Login
The Internet Remote Login Standard Is TELNET
Remote Acess Can Display A Desktop
How Remote Desktops Operate
Assessment Of Remote Login And Desktops
Generality Makes Remote Login And Desktops Powerful
Remote Acess Acommodates Multiple Types Of Computers
Unexpected Results From Remote Acess
Summary
Chapter 31 Facilities For Secure Communication
Introduction
The Internet Is Unse ure
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 Acess From A Distance (VPNs)
Introduction
Organizations Grant Employees Special Privileges
Traveling Employees Lose Privilege
Telecommuters Do Not Have Privilege
Dedicated Leased Cir uits Allow Secure Telecommuting
Standard Internet Connections Are Low-Cost
Can A Te hnology Combine Advantages?
A Virtual Private Network Solves The Problem
How A VPN Works
The Illusion Of A Direct Connection
Signifi an e Of VPNs
Chapter 33 Internet E onomics And Electroni Commerce
Introduction
Who Pays For The Internet?
E-commerce Is Big Business
Security Te hnology Made E-commerce Possible
Secure Sockets
Publi Key En ryption Provides Authenticity
Digital Signatures
Certificates Contain Public Keys
What Is Digital Money?
Digital Cash Is Not Widely Available
Business And E-commerce
The Controversies Over Taxation And Net Neutrality
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?
Appendix 1 Glossary Of Internet Terms
Index
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