Chapter 10 Firewalls
P-660HWP-Dx User’s Guide
37
10.3.1 Denial of Service Attacks
Figure 92
Firewall Application
10.4 Denial of Service
Denials of Service (DoS) attacks are aimed at devices and networks with a connection to the
Internet. Their goal is not to steal information, but to disable a device or network so users no
longer have access to network resources. The P-660HWP-Dx is pre-configured to
automatically detect and thwart all known DoS attacks.
10.4.1 Basics
Computers share information over the Internet using a common language called TCP/IP. TCP/
IP, in turn, is a set of application protocols that perform specific functions. An “extension
number”, called the "TCP port" or "UDP port" identifies these protocols, such as HTTP
(Web), FTP (File Transfer Protocol), POP3 (E-mail), etc. For example, Web traffic by default
uses TCP port 80.
When computers communicate on the Internet, they are using the client/server model, where
the server "listens" on a specific TCP/UDP port for information requests from remote client
computers on the network. For example, a Web server typically listens on port 80. Please note
that while a computer may be intended for use over a single port, such as Web on port 80,
other ports are also active. If the person configuring or managing the computer is not careful, a
hacker could attack it over an unprotected port.
Some of the most common IP ports are:
Table 55
Common IP Ports
21
FTP
53
DNS
23
Telnet
80
HTTP
25
SMTP
110
POP3
Содержание 802.11g HomePlug AV ADSL2+ Gateway P-660HWP-Dx
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Страница 7: ...Safety Warnings P 660HWP Dx User s Guide 39 ...
Страница 8: ...Safety Warnings P 660HWP Dx User s Guide 40 ...
Страница 10: ...Contents Overview P 660HWP Dx User s Guide 36 ...
Страница 20: ...Table of Contents P 660HWP Dx User s Guide 44 ...
Страница 32: ...List of Tables P 660HWP Dx User s Guide 40 ...
Страница 33: ...35 PART I Introduction Introducing the P 660HWP Dx 35 Introducing the Web Configurator 43 ...
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Страница 41: ...Chapter 1 Introducing the P 660HWP Dx P 660HWP Dx User s Guide 41 Figure 7 P 660HWP Dx with ISDN ...
Страница 42: ...Chapter 1 Introducing the P 660HWP Dx P 660HWP Dx User s Guide 42 ...
Страница 56: ...Chapter 2 Introducing the Web Configurator P 660HWP Dx User s Guide 48 ...
Страница 57: ...35 PART II Wizards Wizard Setup for Internet Wireless Access 59 Bandwidth Management Wizard 73 ...
Страница 58: ...36 ...
Страница 78: ...Chapter 4 Bandwidth Management Wizard P 660HWP Dx User s Guide 54 ...
Страница 80: ...36 ...
Страница 98: ...Chapter 5 WAN Setup P 660HWP Dx User s Guide 52 ...
Страница 142: ...Chapter 8 Powerline P 660HWP Dx User s Guide 42 ...
Страница 155: ...35 PART IV Security Firewalls 157 Firewall Configuration 169 Content Filtering 191 Certificates 195 ...
Страница 156: ...36 ...
Страница 176: ...Chapter 11 Firewall Configuration P 660HWP Dx User s Guide 54 Figure 99 Firewall Edit Rule ...
Страница 190: ...Chapter 11 Firewall Configuration P 660HWP Dx User s Guide 68 ...
Страница 194: ...Chapter 12 Content Filtering P 660HWP Dx User s Guide 72 ...
Страница 218: ...36 ...
Страница 222: ...Chapter 14 Static Route P 660HWP Dx User s Guide 38 ...
Страница 238: ...Chapter 16 Dynamic DNS Setup P 660HWP Dx User s Guide 38 ...
Страница 250: ...Chapter 17 Remote Management Configuration P 660HWP Dx User s Guide 46 ...
Страница 262: ...Chapter 18 Universal Plug and Play UPnP P 660HWP Dx User s Guide 58 ...
Страница 263: ...35 PART VI Maintenance and Troubleshooting System 265 Logs 271 Tools 289 Diagnostic 295 Troubleshooting 297 ...
Страница 264: ...36 ...
Страница 270: ...Chapter 19 System P 660HWP Dx User s Guide 40 ...
Страница 288: ...Chapter 20 Logs P 660HWP Dx User s Guide 52 ...
Страница 294: ...Chapter 21 Tools P 660HWP Dx User s Guide 40 ...
Страница 304: ...36 ...
Страница 340: ...Appendix C Internal SPTGEN P 660HWP Dx User s Guide 50 ...
Страница 364: ...Appendix E IP Subnetting P 660HWP Dx User s Guide 42 ...
Страница 368: ...Appendix F Command Interpreter P 660HWP Dx User s Guide 38 ...
Страница 388: ...Appendix K Legal Information P 660HWP Dx User s Guide 38 ...
Страница 394: ...Appendix L Customer Support P 660HWP Dx User s Guide 40 ...
Страница 402: ...Index P 660HWP Dx User s Guide 42 ...