ZyXEL Communications Prestige 480 - Manual (Page 143)

Prestige 480 Dual BRI ISDN Router
Filter Configuration 9-1
Chapter 9
Filter Configuration
This chapter shows you how to create and apply filter(s).
9.1 About Filtering
Your Prestige uses filters to decide whether or not to allow passage of a packet. Data filters are further
divided into incoming and outgoing filters, depending o n the direction of the packet relative to a port.
The following sections describe how to configure filter sets. Please see our application notes for more
information and examples on creating and configuring filters
The Filter Structure of the Prestige
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 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 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.
The following diagram illustrates the logic flow when executing a filter rule.