ZyXEL VoIP Router Prestige 2602R-61 91-006-024004 Manual Do Utilizador

Prestige 2602R Series User’s Guide

Chapter 30 Filter Configuration

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This section shows you how to configure a generic filter rule. The purpose of generic rules is 
to allow you to filter non-IP packets. For IP, it is generally easier to use the IP rules directly.

For generic rules, the Prestige treats a packet as a byte stream as opposed to an IP packet. You 
specify the portion of the packet to check with the Offset (from 0) and the Length fields, both 
in bytes. The Prestige applies the Mask (bit-wise ANDing) to the data portion before 
comparing the result against the Value to determine a match. The Mask and Value fields are 
specified in hexadecimal numbers. Note that it takes two hexadecimal digits to represent a 
byte, so if the length is 4, the value in either field will take 8 digits, for example, FFFFFFFF. 

To configure a generic rule select an empty filter set in menu 21, for example 5.  Select 
Generic Filter Rule in the Filter Type field and press [ENTER] to open Menu 21.1.5.1 – 
Generic Filter Rule, as shown in the following figure.

Figure 175   Menu 21.1.5.1 Generic Filter Rule 

The next table describes the fields in the Generic Filter Rule menu.

Menu 21.1.5.1 - Generic Filter Rule

Filter #: 5,1
Filter Type= Generic Filter Rule
Active= No
Offset= 0
Length= 0
Mask= N/A
Value= N/A
More= No           Log= None
Action Matched= Check Next Rule
Action Not Matched= Check Next Rule

Press ENTER to Confirm or ESC to Cancel:

Table 97   Menu 21.1.5.1 Generic Filter Rule 

Filter #

This is the filter set, filter rule coordinates, for instance, 2, 3 refers to the second filter 

set and the third rule of that set.

Filter Type

Press [SPACE BAR] and then [ENTER] to select a type of rule. Parameters displayed 

below each type will be different. Choices are Generic Filter Rule or TCP/IP Filter 

Rule.

Active

Select Yes to turn on or No to turn off the filter rule.

Offset

Type the starting byte of the data portion in the packet that you want to compare. The 

range for this field is from 0 to 255.

Length

Type the byte count of the data portion in the packet that you want to compare. The 

range for this field is 0 to 8.

Mask

Type the mask (in Hexadecimal) to apply to the data portion before comparison.

Value

Type the value (in Hexadecimal) to compare with the data portion.