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P-660H/HW/W-T Series User’ Guide
129
Chapter 10 Firewalls
• Always shred confidential information, particularly about your computer, before
throwing it away. Some hackers dig through the trash of companies or individuals for
information that might help them in an attack.
10.7 Packet Filtering Vs Firewall
Below are some comparisons between the Prestige’s filtering and firewall functions.
10.7.1 Packet Filtering:
• The router filters packets as they pass through the router’s interface according to the filter
rules you designed.
• Packet filtering is a powerful tool, yet can be complex to configure and maintain,
especially if you need a chain of rules to filter a service.
• Packet filtering only checks the header portion of an IP packet.
10.7.1.1 When To Use Filtering
• To block/allow LAN packets by their MAC addresses.
• To block/allow special IP packets which are neither TCP nor UDP, nor ICMP packets.
• To block/allow both inbound (WAN to LAN) and outbound (LAN to WAN) traffic
between the specific inside host/network "A" and outside host/network "B". If the filter
blocks the traffic from A to B, it also blocks the traffic from B to A. Filters can not
distinguish traffic originating from an inside host or an outside host by IP address.
• To block/allow IP trace route.
10.7.2 Firewall
• The firewall inspects packet contents as well as their source and destination addresses.
Firewalls of this type employ an inspection module, applicable to all protocols, that
understands data in the packet is intended for other layers, from the network layer (IP
headers) up to the application layer.
• The firewall performs stateful inspection. It takes into account the state of connections it
handles so that, for example, a legitimate incoming packet can be matched with the
outbound request for that packet and allowed in. Conversely, an incoming packet
masquerading as a response to a nonexistent outbound request can be blocked.
• The firewall uses session filtering, i.e., smart rules, that enhance the filtering process and
control the network session rather than control individual packets in a session.
• The firewall provides e-mail service to notify you of routine reports and when alerts
occur.
10.7.2.1 When To Use The Firewall
• To prevent DoS attacks and prevent hackers cracking your network.
Содержание P-660H - VERSION 3.40
Страница 1: ...P 660H HW W T Series ADSL 2 Gateway User s Guide Version 3 40 6 2005...
Страница 9: ...P 660H HW W T Series User Guide 9 Customer Support...
Страница 31: ...P 660H HW W T Series User Guide 31 List of Figures...
Страница 37: ...P 660H HW W T Series User Guide 37 List of Tables...
Страница 41: ...P 660H HW W T Series User Guide 41 Introduction to DSL...
Страница 61: ...P 660H HW W T Series User Guide 61 Chapter 3 Wizard Setup for Internet Access...
Страница 89: ...P 660H HW W T Series User Guide 89 Chapter 5 Wireless LAN...
Страница 131: ...P 660H HW W T Series User Guide 131 Chapter 10 Firewalls...
Страница 161: ...P 660H HW W T Series User Guide 161 Chapter 13 Remote Management Configuration...
Страница 175: ...P 660H HW W T Series User Guide 175 Chapter 14 Universal Plug and Play UPnP...
Страница 181: ...P 660H HW W T Series User Guide 181 Chapter 15 Logs Screens...
Страница 195: ...P 660H HW W T Series User Guide 195 Chapter 16 Media Bandwidth Management Advanced Setup...
Страница 207: ...P 660H HW W T Series User Guide 207 Chapter 17 Maintenance...
Страница 217: ...P 660H HW W T Series User Guide 217 Chapter 19 Menu 1 General Setup...
Страница 221: ...P 660H HW W T Series User Guide 221 Chapter 20 Menu 2 WAN Backup Setup...
Страница 225: ...P 660H HW W T Series User Guide 225 Chapter 21 Menu 3 LAN Setup...
Страница 229: ...P 660H HW W T Series User Guide 229 Chapter 22 Wireless LAN Setup...
Страница 235: ...P 660H HW W T Series User Guide 235 Chapter 23 Internet Access...
Страница 249: ...P 660H HW W T Series User Guide 249 Chapter 25 Static Route Setup...
Страница 253: ...P 660H HW W T Series User Guide 253 Chapter 26 Bridging Setup...
Страница 269: ...P 660H HW W T Series User Guide 269 Chapter 27 Network Address Translation NAT...
Страница 285: ...P 660H HW W T Series User Guide 285 Chapter 29 Filter Configuration...
Страница 305: ...P 660H HW W T Series User Guide 305 Chapter 32 System Information and Diagnosis...
Страница 317: ...P 660H HW W T Series User Guide 317 Chapter 33 Firmware and Configuration File Maintenance...
Страница 323: ...P 660H HW W T Series User Guide 323 Chapter 34 System Maintenance...
Страница 327: ...P 660H HW W T Series User Guide 327 Chapter 35 Remote Management...
Страница 337: ...P 660H HW W T Series User Guide 337 Chapter 36 IP Policy Routing...
Страница 341: ...P 660H HW W T Series User Guide 341 Chapter 37 Call Scheduling...
Страница 353: ...P 660H HW W T Series User Guide 353 Chapter 38 Troubleshooting Figure 232 Security Setting ActiveX Controls...
Страница 357: ...P 660H HW W T Series User Guide 357 Appendix A...
Страница 359: ...P 660H HW W T Series User Guide 359 Appendix B...
Страница 383: ...P 660H HW W T Series User Guide 383 Appendix D...
Страница 387: ...P 660H HW W T Series User Guide 387 Appendix F...
Страница 393: ...P 660H HW W T Series User Guide 393 Appendix G...
Страница 397: ...P 660H HW W T Series User Guide 397 Appendix H...
Страница 400: ...P 660H HW W T Series User Guide Appendix I 400...
Страница 401: ...P 660H HW W T Series User Guide 401 Appendix I...
Страница 455: ...P 660H HW W T Series User Guide 455 Appendix M...