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Prestige 128IMH ISDN Modem/ Router/Hub
Filter Configuration 10-11
10.3.2 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/IPX packets. For IP and IPX packets, it is generally easier to use the IP
and IPX rules directly.
For generic rules, the Prestige treats a packet as a byte stream as opposed to an IP or IPX 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 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, e.g.,
FFFFFFFF
.
To configure a generic rule, select Generic Filter Rule in the Filter Type field and press Enter to
open Menu 21.1.2 - Generic Filter Rule, as shown below.
Figure 10-5 Menu 21.1.2 - Generic Filter Rule
Menu 21.1.2 - Generic Filter Rule
Filter #: 1,1
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: