Motorola Netopia Embedded Software Handbook page 303

Adding filters to a filter set
There are two kinds of filters you can add to a filter set: input and output. Input filters check packets received
from the Internet, destined for your network. Output filters check packets transmitted from your network to the
Internet.
Packets in the Motorola Netopia® Embedded Software Version 8.7.4 pass through an input filter if they originate in the WAN and
through an output filter if they're being sent out to the WAN.
The process for adding input and output filters is exactly the same. The main difference between the two
involves their reference to source and destination. From the perspective of an input filter, your local network is
the destination of the packets it checks, and the remote network is their source. From the perspective of an
output filter, your local network is the source of the packets, and the remote network is their destination.
Type of filter
Input filter
Output filter
To add a filter, select Display/Change Filter Set in the Filter Set screen. From the pop-up menu, select the filter
set to which you will add a filter. The Display/Change Filter Set screen appears.
WAN
output filter
The remote network
The local network
packet
input filter
packet
The Motorola Netopia
Source means
LAN
®
Router
Destination means
The local network
The remote network
Security 10-29