The Filter Structure Of The Prestige - ZyXEL Communications Prestige 310 User Manual

Prestige 310 Broadband Sharing Gateway

7.1.1 The Filter Structure of the Prestige

A filter set consists of one or more filter rules. Usually, you would group related rules, for example, all the
rules for NetBIOS, into a single set and give it a descriptive name. The Prestige 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.
Three sets of factory default filter rules have been configured in menu 21 to prevent NetBIOS traffic from
triggering calls and to prevent incoming telnetting and FTP connections from the WAN side. 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.
7-2 Filter Configuration