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Figure 4-24

2.

Enter the following data:

¾

Destination IP Address:

The

Destination IP Address

is the address of the network or host

that you want to assign to a static route.

¾

Subnet Mask:

The

Subnet Mask

determines which portion of an IP Address is the network

portion, and which portion is the host portion.

¾

Gateway:

Here you should type the Gateway address correctly, and the option for

Interface

will adopt the default Gateway address for the Static Route.

¾

Interface:

Select the Interface name in the text box, or else, the default Use Interface will be

adopted for the Static Route.

¾

Status:

Select

Enabled

or

disabled

from the drop-down list

.

3.

Click

Save

to save your settings as shown in Figure 4-24.

To modify or delete an existing entry:

1.

Find the desired entry in the table.

2.

Click

Edit

as desired on the

Edit

column.

Click the

Enable/ Disabled Selected

button to make selected entries enabled/ disabled.

Click the

Delete Selected

button to delete selected entries.

4.6.3 RIP Settings

Choose “

Route Settings

”

Æ

“

RIP Settings

”, you can see the RIP (Routing Information Protocol)

screen which allows you to configure the RIP.

Figure 4-25

)

Note:

RIP cannot be configured on the WAN Interface which has NAT enabled (such as PPPoE).

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4.7 Forwarding

There are four submenus under the Forwarding menu:

Virtual Servers

,

Port Triggering

,

DMZ

and

UPnP

. Click any of them, and you will be able to configure the corresponding function.

4.7.1 Virtual Servers

Choose menu “

Forwarding

”

→

“

Virtual Servers

”, and then you can view and add virtual servers

in the next screen (shown in Figure 4-26). Virtual servers can be used for setting up public

services on your LAN. A virtual server is defined as a service port, and all requests from Internet

to this service port will be redirected to the computer specified by the server IP. Any PC that was

used for a virtual server must have a static or reserved IP address because its IP address may

change when using the DHCP function.

Figure 4-26

¾

Service Port:

The numbers of External Service Ports. You can enter a service port or a

range of service ports (the format is XXX – YYY; XXX is the Start port and YYY is the End

port).

¾

IP Address

: The IP address of the PC running the service application.

¾

Protocol

: The protocol used for this application, either

TCP

,

UDP

, or

All

(all protocols

supported by the Modem Router).

¾

Status

: The status of this entry, "Enabled" means the virtual server entry is enabled.

¾

Edit

: To modify or delete an existing entry.

To setup a virtual server entry:

1.

Click the

Add New

button. (pop-up

Figure 4-27)

2.

Select the service you want to use from the

Common Service Port

list. If the

Common

Service Port

menu does not list the service that you want to use, enter the number of the

service port or service port range in the

Service Port

field.

3.

Select the service you want to use from the

Use Interface

list.

4.

Enter the IP address of the computer running the service application in the

IP Address

field.

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5.

Select the protocol used for this application in the

Protocol

drop-down list, either

TCP

,

UDP

,

or

All

.

6.

Select the

Enabled

option in the

Status

drop-down list.

Click the

Save

button.

Figure 4-27

)

Note:

It is possible that you have a computer or server that has more than one type of available service.

If so, select another service, and type the same IP address for that computer or server.

To modify or delete an existing entry:

1.

Find the desired entry in the table.

2.

Click

Edit

as desired on the

Edit

column.

Click the

Enable/ Disabled Selected

button to make selected entries enabled/ disabled.

Click the

Delete Selected

button to delete selected entries.

)

Note:

If you set the service port of the virtual server as 80, you must set the Web management port on

System Tools –> Remote Management

page to be any other value except 80 such as 8080.

Otherwise there will be a conflict to disable the virtual server.

4.7.2 Port Triggering

Choose menu “

Forwarding

”

→

”

Port Triggering

”, you can view and add port triggering in the

next screen (shown in Figure 4-28). Some applications require multiple connections, like Internet

games, video conferencing, Internet telephoning and so on. Port Triggering is used for some of

these applications that cannot work with a pure NAT Modem Router.

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Figure 4-28

To add a new rule, follow the steps below.

1.

Click the

Add New

button, the next screen will pop-up as shown in Figure 4-29.

2.

Select a common application from the

Common Service Port

drop-down list, then the

Trigger Port

field and the

Open Ports

field will be automatically filled. If the

Common

Service Port

do not have the application you need, enter the

Trigger Port

and the

Open

Ports

manually.

3.

Select the protocol used for Trigger Port from the

Trigger Protocol

drop-down list, either

TCP

,

UDP

, or

All

.

4.

Select the protocol used for Incoming Ports from the

Incoming Protocol

drop-down list,

either

TCP

or

UDP

, or

All.

5.

Select

Enable

in

Status

field.

6.

Click the

Save

button to save the new rule.

Figure 4-29

¾

Trigger Port

: The port for outgoing traffic. An outgoing connection using this port will trigger

this rule.

¾

Trigger Protocol

: The protocol used for Trigger Ports, either

TCP

,

UDP

, or

All

(all protocols

supported by the Modem Router).

¾

Open Port

: The port or port range used by the remote system when it responds to the

outgoing request. A response using one of these ports will be forwarded to the PC which

triggered this rule. You can input at most 5 groups of ports (or port sections). Every group of

ports must be separated with ",", for example, 2000-2038, 2046, 2050-2051, 2085,

3010-3030.

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¾

Open Protocol

: The protocol used for

Incoming Port

, either

TCP

,

UDP

, or

ALL

(all

protocols supported by the Modem Router).

¾

Status

: The status of this entry, Enabled means the Port Triggering entry is enabled.

¾

Modify

: To modify or delete an existing entry.

¾

Common Service Port

: Some popular applications already listed in the drop-down list of

Open Protocol

.

To modify or delete an existing entry:

1.

Find the desired entry in the table.

2.

Click

Edit

as desired on the

Edit

column.

Click the

Enable/ Disabled Selected

button to make selected entries enabled/ disabled.

Click the

Delete Selected

button to delete selected entries.

Once the Modem Router is configured, the operation is as follows:

1.

A local host makes an outgoing connection to an external host using a destination port

number defined in the

Trigger Port

field.

2.

The Modem Router records this connection, opens the incoming port or ports associated

with this entry in the

Port Triggering

table, and associates them with the local host.

3.

When necessary, the external host will be able to connect to the local host using one of the

ports defined in the

Incoming Ports

field.

)

Note:

1.

When the trigger connection is released, the corresponding opened ports will be closed.

2.

Each rule can only be used by one host on the LAN at a time. The trigger connection of other

hosts on the LAN will be refused.

3.

Open Ports

ranges cannot overlap each other.

4.7.3 DMZ

Choose menu “

Forwarding

→

DMZ

”, and then you can view and configure DMZ host in the screen

(shown in Figure 4-30).The DMZ host feature allows one local host to be exposed to the Internet

for a special-purpose service such as Internet gaming or videoconferencing. The Modem Router

forwards packets of all services to the DMZ host. Any PC whose port is being forwarded must

have its DHCP client function disabled and should have a new static IP Address assigned to it

because its IP Address may be changed when using the DHCP function.

Figure 4-30