Firewall Versus Filters; Applying A Filter; Applying Lan Filters; Figure 149 Protocol And Device Filter Sets - ZyXEL Communications P-202H V2 User Manual

Figure 149 Protocol and Device Filter Sets

25.5 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.

25.6 Applying a Filter

This section shows you where to apply the filter(s) after you design it (them). The ZyXEL
Device 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.

25.6.1 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. The factory default filter set,
NetBIOS_LAN, is inserted in the protocol filters field under Input Filter Sets in menu 3.1 in
order to prevent local NetBIOS messages from triggering calls to the DNS server. Input filter
sets filter incoming traffic to the ZyXEL Device and output filter sets filter outgoing traffic
from the ZyXEL Device.
Chapter 25 Filter Configuration
P-202H Plus v2 User's Guide
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