Prestige 661H/HW Series User’s Guide
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Chapter 11 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.
11.7 Packet Filtering Vs Firewall
Below are some comparisons between the Prestige’s filtering and firewall functions.
11.7.1 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.
11.7.1.1 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.
11.7.2 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.
11.7.2.1 When To Use The Firewall
• To prevent DoS attacks and prevent hackers cracking your network.
Содержание Prestige 661H Series
Страница 37: ...Prestige 661H HW Series User s Guide 37 List of Tables...
Страница 41: ...Prestige 661H HW Series User s Guide 41 Introduction to DSL...
Страница 51: ...Prestige 661H HW Series User s Guide 51 Chapter 1 Getting To Know Your Prestige...
Страница 67: ...Prestige 661H HW Series User s Guide 67 Chapter 3 Wizard Setup for Internet Access...
Страница 81: ...Prestige 661H HW Series User s Guide 81 Chapter 5 LAN Setup...
Страница 125: ...Prestige 661H HW Series User s Guide 125 Chapter 8 Network Address Translation NAT Screens...
Страница 143: ...Prestige 661H HW Series User s Guide 143 Chapter 11 Firewalls...
Страница 151: ...Prestige 661H HW Series User s Guide 151 Chapter 12 Firewall Configuration Figure 64 Firewall Edit Rule...
Страница 165: ...Prestige 661H HW Series User s Guide 165 Chapter 12 Firewall Configuration...
Страница 169: ...Prestige 661H HW Series User s Guide 169 Chapter 13 Content Filtering...
Страница 175: ...Prestige 661H HW Series User s Guide 175 Chapter 14 Introduction to IPSec...
Страница 203: ...Prestige 661H HW Series User s Guide 203 Chapter 15 VPN Screens...
Страница 207: ...Prestige 661H HW Series User s Guide 207 Chapter 16 Remote Management Configuration...
Страница 221: ...Prestige 661H HW Series User s Guide 221 Chapter 17 Universal Plug and Play UPnP...
Страница 227: ...Prestige 661H HW Series User s Guide 227 Chapter 18 Logs Screens...
Страница 241: ...Prestige 661H HW Series User s Guide 241 Chapter 19 Media Bandwidth Management Advanced Setup...
Страница 265: ...Prestige 661H HW Series User s Guide 265 Chapter 21 Maintenance...
Страница 275: ...Prestige 661H HW Series User s Guide 275 Chapter 23 Menu 1 General Setup...
Страница 279: ...Prestige 661H HW Series User s Guide 279 Chapter 24 Menu 2 WAN Backup Setup...
Страница 283: ...Prestige 661H HW Series User s Guide 283 Chapter 25 Menu 3 LAN Setup...
Страница 287: ...Prestige 661H HW Series User s Guide 287 Chapter 26 Wireless LAN Setup...
Страница 293: ...Prestige 661H HW Series User s Guide 293 Chapter 27 Internet Access...
Страница 307: ...Prestige 661H HW Series User s Guide 307 Chapter 29 Static Route Setup...
Страница 311: ...Prestige 661H HW Series User s Guide 311 Chapter 30 Bridging Setup...
Страница 327: ...Prestige 661H HW Series User s Guide 327 Chapter 31 Network Address Translation NAT...
Страница 343: ...Prestige 661H HW Series User s Guide 343 Chapter 33 Filter Configuration...
Страница 363: ...Prestige 661H HW Series User s Guide 363 Chapter 36 System Information and Diagnosis...
Страница 375: ...Prestige 661H HW Series User s Guide 375 Chapter 37 Firmware and Configuration File Maintenance...
Страница 381: ...Prestige 661H HW Series User s Guide 381 Chapter 38 System Maintenance...
Страница 385: ...Prestige 661H HW Series User s Guide 385 Chapter 39 Remote Management...
Страница 395: ...Prestige 661H HW Series User s Guide 395 Chapter 40 IP Policy Routing...
Страница 399: ...Prestige 661H HW Series User s Guide 399 Chapter 41 Call Scheduling...
Страница 411: ...Prestige 661H HW Series User s Guide 411 Chapter 42 VPN IPSec Setup...
Страница 415: ...Prestige 661H HW Series User s Guide 415 Chapter 43 SA Monitor...
Страница 427: ...Prestige 661H HW Series User s Guide 427 Chapter 44 Troubleshooting Figure 275 Security Setting ActiveX Controls...
Страница 431: ...Prestige 661H HW Series User s Guide 431 Appendix A...
Страница 451: ...Prestige 661H HW Series User s Guide 451 Appendix C IP Subnetting...
Страница 455: ...Prestige 661H HW Series User s Guide 455 Appendix E Command Interpreter...
Страница 461: ...Prestige 661H HW Series User s Guide 461 Appendix F Firewall Commands...
Страница 464: ...Prestige 661H HW Series User s Guide Appendix G NetBIOS Filter Commands 464...
Страница 465: ...Prestige 661H HW Series User s Guide 465 Appendix G NetBIOS Filter Commands...
Страница 478: ...Prestige 661H HW Series User s Guide Appendix H VPN Setup 478 ftp 5631148 bytes sent in 614 8Seconds 9 17Kbytes sec...
Страница 479: ...Prestige 661H HW Series User s Guide 479 Appendix H VPN Setup...
Страница 482: ...Prestige 661H HW Series User s Guide Appendix I Splitters and Microfilters 482...
Страница 483: ...Prestige 661H HW Series User s Guide 483 Appendix I Splitters and Microfilters...
Страница 537: ...Prestige 661H HW Series User s Guide 537 Appendix M Internal SPTGEN...