Prestige 1600 Universal Access Concentrator

Chapter 10

Filter Configuration

This chapter shows you how to create and apply filter(s).

10.1About Filtering

Your Prestige uses filters to decide whether to allow passage of a data packet and/or to make a call. There are two types of filter applications: data filtering and call filtering. Filters are subdivided into device and protocol filters, which are discussed later.

Data filtering screens the data to determine if the packet should be allowed to pass. Data filters are divided into incoming and outgoing filters, depending on the direction of the packet relative to a port. Data filtering can be applied on either the WAN side or the LAN side. Call filtering is used to determine if a packet should be allowed to trigger a call. Outgoing packets must undergo data filtering before they encounter call filtering as shown in the following figure.

 

 

 

 

 

 

 

 

 

 

 

 

Call Filtering

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

No

Built-in

 

No

User-defined

 

No

 

Active Data

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Outgoing

 

 

Data

 

match

 

default

match

 

Call Filters

 

match

 

 

Initiate call

 

Packet

 

 

Filtering

 

 

Call Filters

 

 

 

 

(if applicable)

 

 

 

 

if line not up

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Send packet

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

and reset

 

 

 

 

Match

 

 

 

Match

 

 

 

 

 

Match

 

 

 

 

 

 

Idle Timer

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Drop

 

 

Drop packet

 

 

 

 

 

Drop packet

 

 

 

 

 

 

 

 

 

 

 

 

 

packet

 

 

if line not up

 

 

 

 

 

if line not up

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Or

 

 

 

 

 

 

Or

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Send packet

 

 

 

 

 

Send packet

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

but do not reset

 

 

but do not reset

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Idle Timer

 

 

 

 

 

 

Idle Timer

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure 10-1 Outgoing Packet Filtering Process

The following sections describe how to configure filter sets. Please see the application notes for more information and examples on creating and configuring filters.

10.2The 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.

Filter Configuration

10-1