Configuring A Generic Filter Rule - Nortel BCM50a Configuration Manual

128 Chapter 11 Filter configuration

Configuring a Generic Filter Rule

This section shows you how to configure a generic filter rule. With generic rules
you can filter non-IP packets. For IP packets, it is generally easier to use the IP
rules directly.
For generic rules, the BCM50a Integrated Router 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 BCM50a
Integrated Router applies the Mask (using the bit-wise-AND action) 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, for example, FFFFFFFF.
To configure a generic rule, select Generic Filter Rule in the Filter Type field
in menu 21.1.1.1 and press [ENTER] to open Generic Filter Rule, as shown in
Figure
N0115791
59.