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Step 9

Click

Save/Apply

to apply the settings.

If the application you require is not in the list, manually enter the information.

Select the protocol for the service you are providing from the Protocol drop-down list. Under External Port, enter

the port number of the service you are providing. In the Internal Port field, enter the internal port number, to which

service requests are to be forwarded. In the Local IP Address field, enter the IP address of the PC that provides the

service.

Example

The Web server is configured to react to requests on port 8080. However, the requests from websites enter the Web

server via port 80 (standard value). If you add the PC to the forwarding table and define port 80 as the public port

and port 8080 as an internal port, all requests from the Internet are diverted to the service with port 80 on the Web

server of the PC you have defined with port 8080.

Deleting Port Forwarding

Step 1

Select the

Remove

check box.

Step 2

Click

Save/Apply

to apply the settings.

Port Triggering

If you configure port triggering for a certain application, you must determine a so-called trigger port and the protocol

(TCP or UDP) that this port uses. You then assign the public ports that are to be opened for the application to this

trigger port. You can select known Internet services or manually assign ports or port blocks.

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Adding Port Triggering

Step 1

To set up port triggering for a service, select

Advanced Settings

>

NAT

>

Port Triggering

, and click

Add

.

Step 2

Select the required application from the

Select an application

drop-down list, or manually enter the information in the

Custom

application

field.

Step 3

Trigger Port Start and Trigger Port End:

Enter the port that is to

be monitored for outgoing data traffic.

Trigger Protocol:

Select the protocol that is to be monitored for

outgoing data traffic.

Open Protocol:

Select the protocol that is to be allowed for

incoming data traffic.

Open Port Start and Open Port End:

Enter the port that is to be

opened for incoming traffic.

Step 4

Click

Save/Apply

to apply the settings.

Removing Port Triggering

Step 1

Select the

Remove

check box.

Step 2

Click

Save/Apply

to apply the settings.

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DMZ Host

The demilitarized military zone (DMZ) host feature allows one local computer to be exposed to the Internet. This

function is applicable for:

Users who want to use a special-purpose Internet service, such as an on-line game or video conferencing

±

program, that is not in the port forwarding list and for which no port range information is available.

Users who are not concerned with security and wish to expose one computer to all services without restriction.

±

Note:

A DMZ host is not protected by the firewall and may be vulnerable to attack. This may also put other

computers in the home network at risk. Hence, when designating a DMZ host, you must consider the security impli-

cations and take the appropriate precautions.

You can set up a client in your local network as a DMZ host. Your device then forwards all incoming data traffic

from the Internet to this client. You can, for example, operate your own Web server on one of the clients in your

local network and make it accessible to Internet users. As the exposed host, the local client is directly visible to

the Internet and therefore particularly vulnerable to attacks (for example, hacker attacks). Enable this function only

when necessary (for example, to operate a Web server) and when other functions (for example, port forwarding) are

inadequate. In this case, you should take appropriate measures for the clients concerned.

Note:

Only one PC per public IP address can be set up as an exposed host.

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Adding a DMZ Host

Step 1

To set up a PC as a DMZ host, select

Advanced Setup

> NAT >

DMZ Host.

Step 2

Enter the local IP address of the PC that is to be enabled as an

exposed host.

Step 3

Click

Save/Apply

to apply the settings.

Remove DMZ host

Step 1

Clear the DMZ Host Address.

Step 2

Click

Save/Apply

to apply the settings.

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Select

Advanced Setup >

Security

>

IP Filtering

. The

Outgoing

IP Filtering Setup

page will appear.

By default, the firewall is enabled. The firewall is used to block data

transmissions between the Internet and your PC. It serves as a

security gate and permits only authorized traffic to be sent to the

LAN.

Click

Add

to create an IP Filter Rule.

Security