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12.2.1

The Port Forwarding Screen

Click

Network Setting > NAT

to open the

Port Forwarding

screen.

Figure 42

Network Setting > NAT > Port Forwarding

Table 40

Network Setting > NAT > Port Forwarding

LABEL

DESCRIPTION

WAN Interface

Select the WAN interface for which to configure NAT port forwarding rules.

Add new rule

Click this to add a new port forwarding rule.

Active

This field indicates whether the rule is active or not.

A yellow bulb signifies that this rule is active. A gray bulb signifies that this rule is not

active.

Service Name

This is the service’s name. This shows

User Defined

if you manually added a service.

You can change this by clicking the edit icon.

External Start/End

Port

This is the first/last external port number that identifies a service.

Internal Start/End

Port

This is the first/last internal port number that identifies a service.

Server IP Address

This is the server’s IP address.

Modify

Click the

Edit

icon to edit the port forwarding rule.

Click the

Delete

icon to delete an existing port forwarding rule. Note that subsequent

address mapping rules move up by one when you take this action.

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12.2.2

The Port Forwarding Add/Edit Screen

This screen lets you create or edit a port forwarding rule. Click

Add new rule

in the

Port

Forwarding

screen or the

Edit

icon next to an existing rule.

Figure 43

NAT > Port Forwarding: Add/Edit

Table 41

NAT > Port Forwarding: Add/Edit

LABEL

DESCRIPTION

Active

Select or clear this field to turn the port forwarding rule on or off.

Service Name

Select a service to forward or select

User Defined

and enter a name in the field to the

right.

External Start

Port

Configure this for a user-defined entry. Enter the original destination port for the

packets.

To forward only one port, enter the port number again in the

External End Port

field.

To forward a series of ports, enter the start port number here and the end port number

in the

External End Port

field.

External End Port

Configure this for a user-defined entry. Enter the last port of the original destination

port range.

To forward only one port, enter the port number in the

External Start

Port

field above

and then enter it again in this field.

To forward a series of ports, enter the last port number in a series that begins with the

port number in the

External Start Port

field above.

Server IP Address

Enter the inside IP address of the virtual server here.

Protocol

Select the protocol supported by this virtual server. Choices are

TCP

,

UDP

, or

TCP/UDP

.

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12.3

The Address Mapping Screen

Ordering your rules is important because the Router applies the rules in the order that you specify.

When a rule matches the current packet, the Router takes the corresponding action and the

remaining rules are ignored.

This screen is avaliable only when you select

NAT Full Feature on

in the

General

screen. To change

your Router’s address mapping settings, click

Network Setting > NAT > Address Mapping

.

Network Se ting > NAT > Addre

s Mapping

Table 42

Network > NAT > Address Mapping

LABEL

DESCRIPTION

Add new rule

Click this to add a new address mapping rule.

Mapping Set

This is the index number of the address mapping set.

Local Start IP

This is the starting Inside Local IP Address (ILA).

Local End IP

This is the end Inside Local IP Address (ILA).

Global Start IP

This is the starting Inside Global IP Address (IGA).

Global End IP

This is the ending Inside Global IP Address (IGA).

Type

This is the port mapping type.

Modify

Click the edit icon to go to the screen where you can edit the address mapping rule.

Click the delete icon to delete an existing address mapping rule. Note that subsequent

address mapping rules move up by one when you take this action.

Open Start Port

Configure this for a user-defined entry. This shows the port number to which you want

the Router to translate the incoming port. For a range of ports, enter the first number

of the range to which you want the incoming ports translated.

Open End Port

Configure this for a user-defined entry. This shows the last port of the translated port

range.

Table 41

NAT > Port Forwarding: Add/Edit (continued)

LABEL

DESCRIPTION

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12.3.1

The Address Mapping Rule Edit Screen

Use this screen to edit an address mapping rule. Click the rule’s edit icon in the

Address Mapping

screen to display the screen shown next.

Figure 44

NAT > Address Mapping: Edit

Figure 45

NAT > Address Mapping: Edit

LABEL

DESCRIPTION

Type

Choose the port mapping type from one of the following.

One-to-One:

maps one local IP address to one global IP address. Note that port

numbers do not change for One-to-one NAT mapping type.

Many-to-One:

maps multiple local IP addresses to one global IP address.

Many-to-Many:

maps multiple local IP addresses to shared global IP addresses.

One-to-Many (Server):

allows you to specify inside servers of different services

behind the NAT to be accessible to the outside world.

Local Start IP

Enter the starting local IP address (ILA).

Local End IP

Enter the ending local IP address (ILA).

Global Start IP

Enter the starting global IP address (IGA). Enter 0.0.0.0 here if you have a dynamic IP

address from your ISP.

Global End IP

This is the ending global IP address (IGA).

Mapping Set

Select the index number of the address mapping set.

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12.4

The DMZ Screen

Click

Network Setting > NAT > DMZ

to open the

DMZ

screen. Use this screen to specify the IP

address of a default server to receive packets from ports not specified in the

Port Forwarding

screen.

Figure 46

Network Setting > NAT > DMZ

Table 43

Network Setting > NAT > DMZ

LABEL

DESCRIPTION

WAN Interface

Select the WAN interface for which to configure a default server.

Default Server

Address

Enter the IP address of the default server which receives packets from ports that are not

specified in the

Port Forwarding

screen.

Note: If you do not assign a default server, the Router discards all packets received for

ports not specified in the virtual server configuration.

12.5

The ALG Screen

Click

Network Setting > NAT > ALG

to open the

ALG

screen. Use this screen to enable and disable

the NAT Application Layer Gateway (ALG) in the Router.