ZyXEL P-202H Plus User Guide - Page 236

The Filter Structure of the ZyXEL Device

Page 236 highlights

P-202H Plus v2 User's Guide 25.1.1 The Filter Structure of the ZyXEL Device A filter set consists of one or more filter rules. Usually, you would group related rules, e.g., all the rules for NetBIOS, into a single set and give it a descriptive name. The ZyXEL Device allows you to configure up to twelve filter sets with six rules in each set, for a total of 72 filter rules in the system. You cannot mix device filter rules and protocol filter rules within the same set. You can apply up to four filter sets to a particular port to block multiple types of packets. With each filter set having up to six rules, you can have a maximum of 24 rules active for a single port. Sets of factory default filter rules have been configured in menu 21 to prevent NetBIOS traffic from triggering calls and to prevent incoming telnet sessions. A summary of their filter rules is shown in the figures that follow. The following figure illustrates the logic flow when executing a filter rule. See also Figure 144 on page 243 for the logic flow when executing an IP filter. 235 Chapter 25 Filter Configuration

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P-202H Plus v2 User’s Guide
235
Chapter 25 Filter Configuration
25.1.1
The Filter Structure of the ZyXEL Device
A filter set consists of one or more filter rules. Usually, you would group related rules, e.g., all
the rules for NetBIOS, into a single set and give it a descriptive name. The ZyXEL Device
allows you to configure up to twelve filter sets with six rules in each set, for a total of 72 filter
rules in the system. You cannot
mix device filter rules and protocol filter rules within the same
set. You can apply up to four filter sets to a particular port to block multiple types of packets.
With each filter set having up to six rules, you can have a maximum of 24 rules active for a
single port.
Sets of factory default filter rules have been configured in menu 21 to prevent NetBIOS traffic
from triggering calls and to prevent incoming telnet sessions. A summary of their filter rules is
shown in the figures that follow.
The following figure illustrates the logic flow when executing a filter rule. See also
Figure 144
on page 243
for the logic flow when executing an IP filter.