ZyXEL Communications G-2000 Plus User Manual

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ZyAIR G-2000 Plus User’s Guide
Chapter 29 Filter Configuration
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Figure 178   Protocol and Device Filter Sets
29.5  Firewall Versus Filters
Firewall configuration is discussed in the firewall chapters of this manual. Further 
comparisons are also made between filtering, NAT and the firewall. 
29.6  Applying a Filter 
This section shows you where to apply the filter(s) after you design it (them). The ZyAIR 
already has filters to prevent NetBIOS traffic from triggering calls, and block incoming telnet, 
FTP and HTTP connections
.
Note: 
If you do not activate the firewall, it is advisable to apply filters
29.6.1  Applying LAN Filters
LAN traffic filter sets may be useful to block certain packets, reduce traffic and prevent 
security breaches. Go to menu 3.1 (shown next) and enter the number(s) of the filter set(s) that 
you want to apply as appropriate. You can choose up to four filter sets (from twelve) by 
entering their numbers separated by commas, e.g., 3, 4, 6, 11. Input filter sets filter incoming 
traffic to the ZyAIR and output filter sets filter outgoing traffic from the ZyAIR. For PPPoE or 
PPTP encapsulation, you have the additional option of specifying remote node call filter sets.