Advanced Settings

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N300 Wireless Gigabit Router WNR3500Lv2

3.

Click the

Add Custom Service

button to display the following screen:

4.

In the Service Name field, enter a descriptive name.

5.

In the Protoco

l

list, select the protocol. If you are unsure, select

TCP/UDP

.

6.

In the Starting Port field, enter the beginning port number.

•

If the application uses a single port, enter the same port number in the Ending Port

field.

•

If the application uses a range of ports, enter the ending port number of the range in

the Ending Port field.

7.

In the Server IP Address field, enter the IP address of your local computer that will provide

this service.

8.

Click

Apply

. The service appears in the list in the Port Forwarding/Port Triggering screen.

Editing or Deleting a Port Forwarding Entry



To edit or delete a port forwarding entry:

1.

In the table, select the radio button next to the service name.

2.

Click

Edit Service

or

Delete Service

.

Application Example: Making a Local Web Server Public

If you host a web server on your local network, you can use port forwarding to allow web

requests from anyone on the Internet to reach your web server.



To make a local web server public:

1.

Assign your web server either a fixed IP address or a dynamic IP address using DHCP

address reservation. In this example, your router will always give your web server an IP

address of 192.168.1.33.

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N300 Wireless Gigabit Router WNR3500Lv2

2.

In the Port Forwarding screen, configure the router to forward the HTTP service to the local

address of your web server at

192.168.1.33

. HTTP (port 80) is the standard protocol for web

servers.

3.

(Optional) Register a host name with a Dynamic DNS service, and configure your router to

use the name as described in

Dynamic DNS

on page 84. To access your web server from

the Internet, a remote user has to know the IP address that has been assigned by your ISP.

However, if you use a Dynamic DNS service, the remote user can reach your server by a

user-friendly Internet name, such as mynetgear.dyndns.org.

Set Up Port Triggering

Port triggering is a dynamic extension of port forwarding that is useful in these cases:

•

More than one local computer needs port forwarding for the same application (but not

simultaneously).

•

An application needs to open incoming ports that are different from the outgoing port.

When port triggering is enabled, the router monitors outbound traffic looking for a specified

outbound “trigger” port. When the router detects outbound traffic on that port, it remembers

the IP address of the local computer that sent the data. The router then temporarily opens the

specified incoming port or ports, and forwards incoming traffic on the triggered ports to the

triggering computer.

While port forwarding creates a static mapping of a port number or range to a single local

computer, port triggering can dynamically open ports to any computer that needs them and

can close the ports when they are no longer needed.

Note:

If you use applications such as multiplayer gaming, peer-to-peer

connections, real-time communications such as instant messaging,

or remote assistance (a feature in Windows XP), you should also

enable Universal Plug and Play (UPnP) according to the instructions

in

Universal Plug and Play

on page 89.

To set up port triggering, you need to know which inbound ports the application needs. Also,

you need to know the number of the outbound port that will trigger the opening of the inbound

ports. You can usually determine this information by contacting the publisher of the

application or user groups or newsgroups.



To set up port triggering:

1.

Select

Advanced >Advancec Setup > Port Forwarding/Port Triggering

.

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83

N300 Wireless Gigabit Router WNR3500Lv2

2.

Select the

Port Triggering

radio button to display the port triggering information.

3.

Clear the

Disable Port Triggering

check box if it is selected.

Note:

If the Disable Port Triggering check box is selected after you configure

port triggering, port triggering is disabled. However, any port triggering

configuration information you added to the router is retained even though it is

not used.

4.

In the Port Triggering Timeout field, enter a value up to 9999 minutes.

5.

This value controls the inactivity timer for the designated inbound ports. The inbound ports

close when the inactivity time expires. This is required because the router cannot be sure

when the application has terminated.

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N300 Wireless Gigabit Router WNR3500Lv2

6.

Click

Add Service

to display the following screen:

7.

In the Service Name field, type a descriptive service name.

8.

In the Service User list, select

Any

(the default) to allow this service to be used by any

computer on the Internet. Otherwise, select

Single address

, and enter the IP address of

one computer to restrict the service to a particular computer.

9.

Select the service type, either

TCP

or

UDP

or both (

TCP/UDP

). If you are not sure, select

TCP/UDP.

10.

In the Triggering Port field, enter the number of the outbound traffic port that will cause the

inbound ports to be opened.

11.

Enter the inbound connection port information in the Connection Type, Starting Port, and

Ending Port fields.

12.

Click

Apply

. The service appears in the Port Triggering Portmap table.

Dynamic DNS

If your Internet service provider (ISP) gave you a permanently assigned IP address, you can

register a domain name and have that name linked with your IP address by public Domain

Name Servers (DNS). However, if your Internet account uses a dynamically assigned IP

address, you do not know in advance what your IP address will be, and the address can

change frequently. In this case, you can use a commercial Dynamic DNS service. This type

of service lets you register your domain to their IP address and forwards traffic directed at

your domain to your frequently changing IP address.

If your ISP assigns a private WAN IP address (such as 192.168.x.x or 10.x.x.x), the Dynamic

DNS service will not work because private addresses are not routed on the Internet.

Your router contains a client that can connect to the Dynamic DNS service provided by

DynDNS.org. First visit their website at

and obtain an account and

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N300 Wireless Gigabit Router WNR3500Lv2

host name that you configure in the router. Then, whenever your ISP-assigned IP address

changes, your router automatically contacts the Dynamic DNS service provider, logs in to

your account, and registers your new IP address. If your host name is hostname, for

example, you can reach your router at

.

On the Advanced tab, select

Advanced Setup > Dynamic DNS

to display the following

screen:

Figure 9. Forward traffic to a changing IP address



To set up Dynamic DNS:

1.

Register for an account with one of the Dynamic DNS service providers whose names

appear in the Service Provider list. For example, for DynDNS.org, select

www.dyndns.org

.

2.

Select the

Use a Dynamic DNS Service

check box.

3.

Select the name of your Dynamic DNS service provider.

4.

Type the host name (or domain name) that your Dynamic DNS service provider gave you.

5.

Type the user name for your Dynamic DNS account. This is the name that you use to log in

to your account, not your host name.

6.

Type the password (or key) for your Dynamic DNS account.

7.

If your Dynamic DNS provider allows the use of wildcards in resolving your URL, you can

select the

Use Wildcards

check box to activate this feature.

For example, the wildcard feature causes

*.yourhost.dyndns.org

to be aliased to the

same IP address as yourhost.dyndns.org.

8.

Click

Apply

to save your configuration.