P-660R-T Series User’s Guide
187
Chapter 22 Filter Configuration
22.5 Filter Types and NAT
There are two classes of filter rules,
Generic Filter
Device rules and Protocol Filter (
TCP/IP
)
rules. Generic Filter rules act on the raw data from/to LAN and WAN. Protocol Filter
rules act
on IP packets.
When NAT (Network Address Translation) is enabled, the inside IP address and port number
are replaced on a connection-by-connection basis, which makes it impossible to know the
exact address and port on the wire. Therefore, the Prestige applies the protocol filters to the
“native” IP address and port number before NAT for outgoing packets and after NAT for
incoming packets. On the other hand, the generic (or device) filters are applied to the raw
packets that appear on the wire. They are applied at the point where the Prestige is receiving
and sending the packets; for instance, the interface. The interface can be an Ethernet, or any
other hardware port. The following figure illustrates this.
Figure 122
Protocol and Device Filter Sets
22.6 Example Filter
Let’s look at an example to block outside users from telnetting into the Prestige.
Action Not
Matched
Select the action for a packet not matching the rule. Choices are
Check Next Rule
,
Forward
or
Drop
.
When you have completed this menu, press [ENTER] at the prompt “
Press ENTER to Confirm
or ESC to Cancel:
” to save your configuration, or press [ESC] at any time to cancel.
Table 57
Menu 21.1.5.1 Generic Filter Rule (continued)
FIELD
DESCRIPTION
Содержание ADSL2+ 4-port Gateway P-660H-D Series
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Страница 23: ...P 660R T Series User s Guide 23 ...
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Страница 31: ...P 660R T Series User s Guide 31 Introduction to DSL ...
Страница 39: ...P 660R T Series User s Guide 39 Chapter 1 Getting To Know Your Prestige ...
Страница 57: ...P 660R T Series User s Guide 57 Chapter 4 Password Setup ...
Страница 65: ...P 660R T Series User s Guide 65 Chapter 5 LAN Setup ...
Страница 75: ...P 660R T Series User s Guide 75 Chapter 6 WAN Setup ...
Страница 87: ...P 660R T Series User s Guide 87 Chapter 7 Network Address Translation NAT Screens ...
Страница 95: ...P 660R T Series User s Guide 95 Chapter 10 Remote Management Configuration ...
Страница 107: ...P 660R T Series User s Guide 107 Chapter 11 Universal Plug and Play UPnP ...
Страница 127: ...P 660R T Series User s Guide 127 Chapter 14 Menu 1 General Setup ...
Страница 131: ...P 660R T Series User s Guide 131 Chapter 15 Menu 2 WAN Backup Setup ...
Страница 135: ...P 660R T Series User s Guide 135 Chapter 16 Menu 3 LAN Setup ...
Страница 157: ...P 660R T Series User s Guide 157 Chapter 19 Static Route Setup ...
Страница 161: ...P 660R T Series User s Guide 161 Chapter 20 Bridging Setup ...
Страница 177: ...P 660R T Series User s Guide 177 Chapter 21 Network Address Translation NAT ...
Страница 205: ...P 660R T Series User s Guide 205 Chapter 24 System Information and Diagnosis ...
Страница 217: ...P 660R T Series User s Guide 217 Chapter 25 Firmware and Configuration File Maintenance ...
Страница 223: ...P 660R T Series User s Guide 223 Chapter 26 System Maintenance ...
Страница 227: ...P 660R T Series User s Guide 227 Chapter 27 Remote Management ...
Страница 237: ...P 660R T Series User s Guide 237 Chapter 28 IP Policy Routing ...
Страница 241: ...P 660R T Series User s Guide 241 Chapter 29 Call Scheduling ...
Страница 253: ...P 660R T Series User s Guide 253 Chapter 30 Troubleshooting Figure 173 Java Sun ...
Страница 257: ...P 660R T Series User s Guide 257 Appendix A ...
Страница 281: ...P 660R T Series User s Guide 281 Appendix C IP Subnetting ...
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Страница 285: ...P 660R T Series User s Guide 285 Appendix D Splitters and Microfilters ...
Страница 287: ...P 660R T Series User s Guide 287 Appendix E Command Interpreter ...
Страница 295: ...P 660R T Series User s Guide 295 Virtual Circuit Topology ...