User's Manual

42
Filtering
The Broadband Home Router uses filters to determine if a data packet should be passed. You
can specify your filter rule on the source side and destination side.
Setting the IP Packet Filter
This page allows you to add new IP packet filter and delete selected IP packet filter. To add a
new filter rule, setting then press apply button. Otherwise, select a required entry to delete it.
Select enable or disable option to decide whether to enable filter function.
Note
If you enable Filtering function, the filter table will display some filter entries
predefined in your device by default. These entries (where source and destination IP
are left as 0.0.0.0 and different service port) allow your network to use various Internet
services. Note that if you delete any one of these predefined entry, the service type of
entry that deletion will block the LAN PCs from accessing its corresponding service.
If you want to filtering a specific computer from accessing certain Internet service or
location, you should create additional filter rule.
Protocol Type: It governs the information flow within a communications infrastructure. You
may select the protocol from drop-down list and then enter the port number that identifies the
service, e.g., web service is on port 80 and FTP on port 21.
Source IP address/subnet mask: If you wish to filter the packet originating from certain
node, enter the IP address which identifies this device on the network. Then enter the subnet
mask where the IP address belongs to.
Destination IP address/subnet mask: If you wish to filter the packet destining for a certain
mode, enter the IP address which identifies this device on the Internet. Then enter the subnet
mask where the IP address belongs to. The field is disregarded if you leave it as 0.0.0.0.
TCP Flags: when protocol type is set with TCP this section should be effective.
Port Range: Enter the starting and ending port number that identify the service that you want
to filter , e.g., web service is on port 80 and FTP on port 21.
Direction: Choose whether to filter the packets that are incoming (In Bound) or outgoing
(Out Bound) on the interface. The action can be Allow or Block.
Each data packet that enters the Broadband Home Router will undergo data filtering. Data
packet is allowed to pass or not depending on whether a match is found.