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ZyAIR Wireless Gateway Series User’s Guide
Filter and Firewall Configuration 24-11
24.3.2 Generic Filter Rule
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 ZyAIR 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 ZyAIR
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 21.1, for example 4. Select
Generic Filter
Rule in the Filter Type field and press [ENTER] to open Menu 21.1.4.1
–
Generic Filter Rule , as shown
in the following figure.
Figure 24-9 Menu 21.1.4.1 Generic Filter Rule
The next table describes the fields in the Generic Filter Rule menu.
Table 24-4 Menu 21.1.4.1 Generic Filter Rule
FIELD DESCRIPTION EXAMPLE
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. 4,1
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 .
Generic Filter
Rule
Active Press [SPACE BAR] to select Yes and press [ENTER] to turn on the
filter rule.
No
(default)
Menu 21.1.4.1 - Generic Filter Rule
Filter #: 4,1
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: