B

Advanced Pages • Advanced IP Filtering Page

Motorola SURFboard SBG941 Series Wireless Cable Modem Gateways • User Guide

33

570280-001-a

Advanced IP Filtering Page

This page allows you to define which local PCs will be denied access to the SBG941

WAN. You can configure IP address filters to block Internet traffic to specific network

devices on the LAN by entering starting and ending IP address ranges.

Note

: Only enter the LSB (Least-significant byte) of the IP address; the upper bytes of

the IP address are set automatically from the IP address for the SBG941 Configuration

Manager.

Field Descriptions for the Advanced IP Filtering Page

Field

Description

Start Address

Enter the starting IP address range of the computers for which you

want to deny access to the SBG941 WAN. Only enter the least

significant byte of the IP address.

End Address

Enter the ending IP address range of the computers you want to

deny access to the SBG941 WAN. Only enter the least significant

byte of the IP address.

Enabled

Activates the IP address filter, when selected.

Select

Enabled

for each range of IP addresses you want to deny

access to the SBG941 WAN.

When done, click

Apply

to activate and save your settings.

B

Advanced Pages • Advanced MAC Filtering Page

Motorola SURFboard SBG941 Series Wireless Cable Modem Gateways • User Guide

34

570280-001-a

Advanced MAC Filtering Page

This page allows you to define up to twenty Media Access Control (MAC) address filters

to prevent PCs from sending outgoing TCP/UDP traffic to the WAN via their MAC

addresses. This is useful because the MAC address of a specific NIC card never

changes, unlike its IP address, which can be assigned via the DHCP server or hard-coded

to various addresses over time.

Field Descriptions for the Advanced MAC Filtering Page

Field

Description

MAC Addresses

Media Access Control address — a unique set of 12 hexadecimal digits

assigned to a PC during manufacturing.

Setting a MAC Address Filter

1.

Enter the MAC address in the MAC Addresses field for the PC you want to block.

2.

Click

Add MAC Address

.

3.

Repeat above steps for up to twenty MAC addresses.

B

Advanced Pages • Advanced Port Filtering Page

Motorola SURFboard SBG941 Series Wireless Cable Modem Gateways • User Guide

35

570280-001-a

Advanced Port Filtering Page

This page allows you to define port filters to prevent all devices from sending outgoing

TCP/UDP traffic to the WAN on specific IP port numbers. By specifying a starting and

ending port range, you can determine what TCP/UDP traffic is allowed out to the WAN

on a per-port basis.

Note:

The specified port ranges are blocked for ALL PCs, and this setting is not IP

address or MAC address specific. For example, to block all PCs on the private LAN from

accessing HTTP sites (or “web surfing”), set the “Start Port” to 80, “End Port” to 80,

“Protocol” to TCP, select

Enabled

, and then click

Apply.

Field Descriptions for the Advanced Port Filtering Page

Field

Description

Start Port

Enter the starting port number.

End Port

Enter the ending port number.

Protocol

Select

TCP

,

UDP

, or

Both

from the drop-down list.

Enabled

Select for each port that you want to activate the IP port filters.

B

Advanced Pages • Advanced Port Forwarding Page

Motorola SURFboard SBG941 Series Wireless Cable Modem Gateways • User Guide

36

570280-001-a

Advanced Port Forwarding Page

This page allows you to run a publicly accessible server on the LAN by specifying the

mapping of TCP/UDP ports to a local PC. This enables incoming requests on specific port

numbers to reach web servers, FTP servers, mail servers, etc. so that they can be

accessible from the public Internet.

A table of commonly used Port numbers is also displayed on the page for your

convenience. The ports used by some common applications are:

•

HTTP: 80

•

FTP: 20, 21

•

Secure Shell: 22

•

Telnet: 23

•

SMTP e-mail: 25

•

SNMP: 161

To map a port, you must enter the range of port numbers that should be forwarded

locally and the IP address to which traffic to those ports should be sent. If only a single

port specification is desired, enter the same port number in the “start” and “end”

locations for that IP address.

B

Advanced Pages • Advanced Port Triggers Page

Motorola SURFboard SBG941 Series Wireless Cable Modem Gateways • User Guide

37

570280-001-a

Advanced Port Triggers Page

This 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, gaming, and some

messaging program features may require these special settings.

The Advanced Port Triggers are similar to Advanced Port Forwarding except that they are

not static ports held open all the time. When the Configuration Manager detects

outgoing data on a specific IP port number set in the “Trigger Range,” the resulting ports

set in the “Target Range” are opened for incoming (sometimes referred to as

bi-directional ports) data. If no outgoing traffic is detected on the “Trigger Range” ports

for 10 minutes, the “Target Range” ports will close. This is a safer method for opening

specific ports for special applications (e.g. video conferencing programs, interactive

gaming, file transfer in chat programs, etc.) because they are dynamically triggered and

not held open constantly or erroneously left open via the router administrator and

exposed for potential hackers to discover.

Field Descriptions for the Advanced Port Triggers Page

Field

Description

Trigger Range

Start Port

The starting port number of the Port Trigger range.