Figure 18. Example of MAC Filtering Page

Table 12. MAC Filtering Menu Option

Option

Description

MAC Address

PCs and other devices can be added to the MAC filter table by

entering their MAC addresses into the

Add MAC Address

box, and

clicking the

Add MAC Address

button. Internet traffic to and from

each listed Address will be blocked.

The Mac Addresses of the computers attached to your network can

be found in the

DHCP Clients

table.

To access the

DHCP Clients

table click on

Basic

on the menu bar then

DHCP

.

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Port Filtering

The Port Filtering page allows you to configure port filters in order to block Internet traffic

to specific ports on all devices on your LAN.

Similarly, you can prevent PCs from sending outgoing TCP/UDP traffic to the Internet

from specific IP port numbers. This can be configured using the Port Filtering page.

To access the

Port Filtering

page:

1

Click

Advanced

in the menu bar.

2

Then click the

Port Filtering

submenu.

Figure 19 shows an example of the menu and Table 11 describes the items you can

select.

Figure 19. Example of Port Filtering Page

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For example

, if you would like to block all PCs on the private LAN from accessing HTTP

sites (or “web surfing”):

1

Set the Start Port to

80

, the End Port to

80

.

2

Set the protocol to

TCP

.

3

Check the

Enable

box to the right of the entry to store settings.

4

Click

Apply

button to activate the filter rules.

Table 13. Port Filtering Menu Option

Option

Description

Start/End Port

Enters the start and end port of the port filter range

Protocol

Filter either both TCP and UDP traffic or just UDP or just TCP.

Forwarding

The Forwarding page allows you to run a publicly accessible server from your LAN by

specifying the mapping of TCP/UDP ports to a local PC. It allows incoming requests to

specific port numbers to reach a web server, FTP server, mail server, etc.

To access the

Forwarding

page,

1

Click

Advanced

in the menu bar.

2

Then click the

Forwarding

submenu.

3

To add a new IPv4 rule, click on the

Create IPv4 Rule

button, to add a new IPv6 rule

click on the

Create IPv6 Rule

.

Most users should select Create IPv4 rule unless

your LAN network is using IPv6.

Figure 20 shows an example of the menu and Table 12 describes the items you can

select.

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Figure 20. Example of Forwarding Page

To activate the port forwarding:

1

Enter the port range of the Internet traffic that you want to forward, and the IP

address of the server to which you want to forward that traffic.

2

Select the protocol(s) to be forwarded.

3

Check the

Enable

box to the bottom of the entry to store settings.

4

Click the

Apply

button to activate the forwarding rules.

Table 14. Forwarding Menu Option

Option

Description

External IP

Address

Enter the External IP address of the device that you want to allow

access to your network. If you do not know the address you can

leave this field blank.

Note:

The External IP Address is not the CM

WAN IP address shown on the status page. It is the address of the

remote device.

External

Start/End Port

Enter the range of port numbers (start and end port) from the

external device that you want to allow onto your network.

If you do

not know the address you can leave this field blank

Local IP

Enter the IP address to which forwarded traffic should be sent. If you

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Address

are creating an IPv4 rule this should be an IPv4 address.

If you are

creating an IPv6 rule this should be an IPv6 address.

Start/End Port

Enter the range of port numbers (start and end port) to forward. If

only a single port is desired, enter the same port number in the

Start

and

End

locations.

Protocol

Select the protocol(s) to be forwarded.

Description

A brief description of the rule you have created.

Enabled

Select ON to enable the rule. For security reasons you should leave

the rule disabled if you are not using it.

Note:

You may need to assign static IP addresses to devices on your LAN to insure that

the port forwarding you have set up will always apply to them.

Port Triggers

The Port Triggers page allows you to configure dynamic triggers to specific devices on

the LAN. This allows for special applications that require specific port numbers with

bi-directional traffic to function properly. Applications such as video conferencing, voice,

gaming, and some messaging program features may require these special settings.

Port Triggers are similar to Port Forwarding except that they are not static ports held

open all the time. With the port triggering function, the Cable Modem/Router detects

outgoing data on a specific IP port number and opens corresponding target ports for

incoming data. If no outgoing traffic is detected on the Trigger Range ports for 10

minutes, the Target Range ports will close.

To access the

Port Triggers

page:

1

Click

Advanced

in the menu bar.

2

Then click the

Port Triggers

submenu.

3

To add a new Port Triggers rule, click on the

Create

button, to add a new rule.

Figure 21 shows an example of the menu and Table 13 describes the items you can

select.

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