P-662H/HW-D Series User’s Guide
Chapter 10 Firewalls
171
• The LAN (Local Area Network) port attaches to a network of computers, which needs
security from the outside world. These computers will have access to Internet services
such as e-mail, FTP, and the World Wide Web. However, “inbound access” will not be
allowed unless you configure remote management or create a firewall rule to allow a
remote host to use a specific service.
10.3.1 Denial of Service Attacks
Figure 90
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 ZyXEL Device 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:
Содержание 802.11g ADSL 2+ 4-Port Security Gateway HW-D Series
Страница 1: ...P 662H HW D Series 802 11g ADSL 2 4 Port Security Gateway User s Guide Version 3 40 Edition 1 7 2006 ...
Страница 2: ......
Страница 10: ...P 662H HW D Series User s Guide 10 Customer Support ...
Страница 24: ...P 662H HW D Series User s Guide 24 Table of Contents ...
Страница 32: ...P 662H HW D Series User s Guide 32 List of Figures ...
Страница 38: ...P 662H HW D Series User s Guide 38 List of Tables ...
Страница 64: ...P 662H HW D Series User s Guide 64 Chapter 2 Introducing the Web Configurator ...
Страница 84: ...P 662H HW D Series User s Guide 84 Chapter 4 Bandwidth Management Wizard ...
Страница 108: ...P 662H HW D Series User s Guide 108 Chapter 5 WAN Setup ...
Страница 122: ...P 662H HW D Series User s Guide 122 Chapter 6 LAN Setup ...
Страница 155: ...P 662H HW D Series User s Guide Chapter 8 DMZ 155 Figure 81 DMZ Private and Public Address Example ...
Страница 156: ...P 662H HW D Series User s Guide 156 Chapter 8 DMZ ...
Страница 188: ...P 662H HW D Series User s Guide 188 Chapter 11 Firewall Configuration Figure 97 Firewall Edit Rule ...
Страница 202: ...P 662H HW D Series User s Guide 202 Chapter 11 Firewall Configuration ...
Страница 210: ...P 662H HW D Series User s Guide 210 Chapter 12 Anti Virus Packet Scan ...
Страница 214: ...P 662H HW D Series User s Guide 214 Chapter 13 Content Filtering ...
Страница 232: ...P 662H HW D Series User s Guide 232 Chapter 14 Content Access Control ...
Страница 238: ...P 662H HW D Series User s Guide 238 Chapter 15 Introduction to IPSec ...
Страница 273: ...P 662H HW D Series User s Guide Chapter 17 Certificates 273 Figure 144 My Certificate Details ...
Страница 284: ...P 662H HW D Series User s Guide 284 Chapter 17 Certificates Figure 152 Trusted Remote Host Details ...
Страница 292: ...P 662H HW D Series User s Guide 292 Chapter 18 Static Route ...
Страница 303: ...P 662H HW D Series User s Guide Chapter 19 Bandwidth Management 303 Figure 162 Bandwidth Management Monitor ...
Страница 304: ...P 662H HW D Series User s Guide 304 Chapter 19 Bandwidth Management ...
Страница 308: ...P 662H HW D Series User s Guide 308 Chapter 20 Dynamic DNS Setup ...
Страница 332: ...P 662H HW D Series User s Guide 332 Chapter 22 Universal Plug and Play UPnP ...
Страница 338: ...P 662H HW D Series User s Guide 338 Chapter 23 System ...
Страница 344: ...P 662H HW D Series User s Guide 344 Chapter 24 Logs ...
Страница 350: ...P 662H HW D Series User s Guide 350 Chapter 25 Tools ...
Страница 363: ...P 662H HW D Series User s Guide Chapter 27 Troubleshooting 363 Figure 213 Security Setting ActiveX Controls ...
Страница 364: ...P 662H HW D Series User s Guide 364 Chapter 27 Troubleshooting ...
Страница 368: ...P 662H HW D Series User s Guide 368 Product Specifications ...
Страница 372: ...P 662H HW D Series User s Guide 372 Appendix C Wall mounting Instructions ...
Страница 408: ...P 662H HW D Series User s Guide 408 Appendix F Wireless LANs ...
Страница 420: ...P 662H HW D Series User s Guide 420 Appendix H Command Interpreter ...
Страница 436: ...P 662H HW D Series User s Guide 436 Appendix L NetBIOS Filter Commands ...
Страница 462: ...P 662H HW D Series User s Guide 462 Appendix M Internal SPTGEN ...
Страница 484: ...P 662H HW D Series User s Guide 484 Appendix P Triangle Route ...