ZyXEL Communications P-335WT User Manual

Page of 485
P-335 Series User’s Guide
Chapter 34 Filter Configuration
344
Figure 206   Protocol and Device Filter Sets
34.5  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. 
34.6  Applying a Filter 
This section shows you where to apply the filter(s) after you design it (them). The Prestige 
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.
34.6.1  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 Prestige and output filter sets filter outgoing traffic from the Prestige. For PPPoE 
or PPTP encapsulation, you have the additional option of specifying remote node call filter 
sets.