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Contents
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Appendix | A | Troubleshooting Norton Personal Firewall |
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| Troubleshoot Norton Personal Firewall problems | 112 |
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| What is wrong with this Web site? | 112 |
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| Why can’t I post information online? | 113 |
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| Why did an email message I sent never arrive? | 113 |
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| Why doesn’t Norton Personal Firewall notify me before |
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| letting programs access the Internet? | 114 |
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| Why can’t I print to a shared computer or connect to a |
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| computer on my local network? | 114 |
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| Why can’t I connect to the Internet via my cable |
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| modem? | 114 |
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| How can a Web site get my browser information? | 115 |
Appendix | B | About the Internet |
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| How information is transmitted over the Internet | 118 |
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| About UDP | 120 |
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| About ICMP | 120 |
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| About IGMP | 120 |
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| How Web information is located on the Internet | 120 |
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| Requesting a page | 121 |
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| Understanding URLs | 121 |
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| How ports identify programs on servers | 122 |
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| How computers are identified on the Internet | 123 |
Appendix | C | Understanding Internet risks |
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| Risks from hackers | 125 |
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| The process of a hacker attack | 125 |
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| Risks from active content | 128 |
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| Risks from inappropriate content and activities | 129 |
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| Blocking site and newsgroup categories | 129 |
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| Restricting access to programs | 129 |
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| Risks to your privacy | 129 |
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| Sending private information | 129 |
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| Understanding cookies | 130 |
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| Blocking cookies | 130 |
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| Tracking Internet use | 131 |
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| Risks from Trojan horses and viruses | 131 |
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| The likelihood of being attacked | 132 |