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Forwarding Web Page (Fig. 29)

For LAN <=> WAN communications, the gateway normally only allows you to originate an

IP connection with a PC on the WAN; it will ignore attempts of the WAN PC to originate a

connection onto your PC. This protects you from malicious attacks from outsiders. However,

sometimes you may wish for anyone outside to be able to originate a connection to a particular

PC on your LAN if the destination port (application) matches one you specify.

This page allows you to specify up to 10 such rules. For example, to specify that outsiders should

have access to an FTP server you have running at 192.168.0.5, create a rule with that address and

Start Port = 20 and End Port = 21 (FTP port ranges) and Protocol = TCP (FTP runs over TCP vs the

other transport protocol, UDP), and click Apply. This will cause inbound packets that match to

be forwarded to that PC rather than blocked. As these connections are not tracked, no entry is

made for them in the Connection Table. The same IP address can be entered multiple times with

different ports.

Fig. 29

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Fig. 30

Port Triggers Web Page (Fig. 30)

Some Internet activities, such as interactive gaming, require that a PC on the WAN side of your

gateway be able to originate connections during the game with your game playing PC on the

LAN side. You could use the Advanced...Forwarding page to construct a forwarding rule during

the game, and then remove it afterwards (to restore full protection to your LAN PC) to facilitate

this. Port Triggering is an elegant mechanism that does this work for you, each time you play the

game.

Port Triggering works as follows. Imagine you want to play a particular game with PCs somewhere

on the Internet. You make a one time effort to set up a Port Trigger for that game, by entering

into Trigger Range the range of destination ports your game will be sending to, and entering into

Target Range the range of destination ports the other player (on the WAN side) will be sending

to (ports your PC’s game receives on). Application programs like games publish this information

in user manuals.

Later, each time you play the game, the gateway automatically creates the

forwarding rule necessary (see Advanced...Forwarding discussion above). This rule is valid until

10 minutes after it sees game activity stop. After 10 minutes, the rule becomes inactive until the

next matched outgoing traffic arrives.

For example, suppose you specify Trigger Range from 6660 to 6670 and Target Range from 113

to 113. An outbound packet arrives at the gateway with your game-playing PC source IP address

192.168.0.10, destination port 6666 over TCP/IP. This destination port is within the Trigger Range,

so the gateway automatically creates a forwarding rule to forward any inbound packets destined

for port 113 to your game-playing PC at 192.168.0.10.

You can specify up to 10 port ranges on which to trigger.

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DMZ Host Web Page (Fig. 31)

Use this page to designate one PC on your LAN that should be left accessible to all PCs from the

WAN side, for all ports. For example, if you put an HTTP server on this machine, anyone will be

able to access that HTTP server by using your gateway IP address as the destination. A setting of

“0” indicates NO DMZ PC.

“Host” is another Internet term for a PC connected to the Internet.

Fig. 31

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Routing Information Protocol Setup Web Page (Fig. 32)

This feature enables the gateway to be used in small business situations where more than one LAN

(local area network) is installed. The RIP protocol provides the gateway a means to "advertise"

available IP routes to these LANs to your cable operator, so packets can be routed properly in this

situation.

Your cable operator will advise you during installation if any setting changes are required here.

Fig. 32

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Firewall Web Pages Group

Web Content Filter and Parental Control Web Pages (Fig. 33 and 34)

These pages allow you to enable, disable, and configure a variety of firewall features associated

with web browsing, which uses the HTTP protocol and transports HTML web pages. On these

pages, you designate the gateway packet types you want to have forwarded or blocked. You can

activate settings by checking them and clicking

Apply

. Here are some of your choices on the

Parental Control page:

•

Activate Keyword Blocking and specify some keywords in the Keyword List to cause blocking

of web pages on the WAN side with the specified keyword in the content.

•

Activate Domain Blocking and specify some Domain Names (e.g. disney.com) in the Domain

List.

Other types of web-related filtering features can be activated from the Web Content Filter page,

including Filter Proxy, Filter Cookies, Filter Java Applets, Filter ActiveX, Filter Popup Windows, and

Firewall Protection.

If you want the gateway to exclude your selected filters to certain computers on your LAN, enter

their MAC addresses in the Trusted Computers area of this page.

Fig. 33

Fig. 34