P-660H/HW/W-T Series User’ Guide

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 172 Menu 21.1.5.1 Generic Filter Rule

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

Log= None

More= No

Action Matched= Check Next Rule

Action Not Matched= Check Next Rule

Press ENTER to Confirm or ESC to Cancel:

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

Table 97 Menu 21.1.5.1 Generic Filter Rule

FIELD

DESCRIPTION

 

 

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.

 

 

More

If Yes, a matching packet is passed to the next filter rule before an action is taken or

 

else the packet is disposed of according to the action fields.

 

If More is Yes, then Action Matched and Action Not Matched will be N/A.

 

 

Chapter 29 Filter Configuration

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