User`s guide

Defining Filters and Firewalls
Overview of Filter profiles
Pipeline User’s Guide Preliminary January 30, 1998 6-9
Generic filter conditions define bits and bytes within a packet. They are applied
to all packet types, including TCP and IP. IP filter conditions are related only to
TCP/IP/UDP packets.
Defining generic filter conditions
If the Type parameter in a filter is set to GENERIC, you can define generic
conditions using these menus:
1
Open Ethernet
>
Filters
>
any profile
2
Determine if you need an Input or Output filter.
3
Open a filter, from 01 to 12, and select Generic
For example:
Forward=No
Offset=14
Length=8
Mask=ffffffffffffffff
Value=aaa030000000080f3
Compare=Equals
More=No
4
Set the Forward parameter. It determines whether the Pipeline will forward a
packet if it matches the definition, where Forward=Yes, or drop the packet if
it matches, where Forward=No.
If a filter is applied as a data filter, the “forward” action determines which
packets will be transmitted and received. If a filter is applied as a call filter,
the “forward” action determines which packets can either initiate a
connection or reset the timer for an established connection.
5
Set Offset, Length, Mask, and Value.
The Offset, Length, Mask, and Value parameters are used to define the exact
location of certain bytes within a packet and the value of those bytes.
6
Set the Compare parameter.
The Compare parameter specifies how a packet’s contents are compared to
the value specified in this filter. After applying the Offset, Mask, and Length
values to reach the appropriate location in a packet, the contents of that
location are compared to the Value parameter. If Compare is set to Equals,
the default, the filter is applied if the packet data are identical to the specified