NETGEAR RangeMax™ Dual Band Wireless-N Router WNDR3300 Reference Manual

Customizing Your Network Settings

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To edit or delete a reserved address entry:

1.

Select the radio button next to the reserved address you want to edit or delete.

2.

Click

Edit

or

Delete

.

Using a Dynamic DNS Service

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, which allows you to register your domain

to their IP address, and forwards traffic directed at your domain to your frequently changing IP

address.

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

DynDNS.org. You must first visit their website at

www.dyndns.org

and obtain an account and host

name, which 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 hostname.dyndns.org.

Note:

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.

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From the main menu of the browser interface, under Advanced, select

Dynamic DNS

to display

the Dynamic DNS screen.

To configure 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.

Figure 4-2

NETGEAR RangeMax™ Dual Band Wireless-N Router WNDR3300 Reference Manual

Customizing Your Network Settings

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v1.0, February 2008

Configuring the WAN Setup Options

The WAN Setup options let you configure a DMZ (demilitarized zone) server, change the

Maximum Transmit Unit (MTU) size, and enable the wireless router to respond to a ping on the

WAN (Internet) port. From the main menu of the browser interface, under Advanced, click

WAN

Setup

to view the WAN Setup screen.

Disabling the SPI Firewall

The Stateful Packet Inspection (SPI) firewall protects your network and computers against attacks

and intrusions. A stateful packet firewall carefully inspects incoming traffic packets, looking for

known exploits such as malformed, oversized, or out-of-sequence packets. The firewall should be

disabled only in special circumstances, such as when you are troubleshooting application issues.

Setting Up a Default DMZ Server

The default DMZ server feature is helpful when you are using some online games and

videoconferencing applications that are incompatible with Network Address Translation (NAT).

The router is programmed to recognize some of these applications and to work correctly with

Figure 4-3

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them, but there are other applications that might not function well. In some cases, one local

computer can run the application correctly if that computer’s IP address is entered as the default

DMZ server.

Incoming traffic from the Internet is usually discarded by the router unless the traffic is a response

to one of your local computers or a service that you have configured in the Port Forwarding/Port

Triggering screen. Instead of discarding this traffic, you can have it forwarded to one computer on

your network. This computer is called the default DMZ server.

The WAN Setup screen lets you configure a default DMZ server.

To assign a computer or server to be a default DMZ server:

1.

In the last

Default DMZ Server

field, type the last digit of the IP address for that computer.

To remove the default DMZ server, enter 0 (zero).

2.

Select the

Default DMZ Server

check box, and click

Apply

.

Responding to a Ping on the Internet (WAN) Port

If you want the router to respond to a ping from the Internet, select the

Respond to Ping on

Internet Port

check box. This should be used only as a diagnostic tool, since it allows your router

to be discovered by Internet scanners. Do not select this check box unless you have a specific

reason to do so, such as when troubleshooting your connection.

Setting the MTU Size

The normal MTU value for most Ethernet networks is 1500 bytes, 1492 bytes for PPPoE

connections, or 1450 for PPTP connections. For some ISPs, you might need to reduce the MTU,

but this is rarely required and should not be done unless you are sure it is necessary for your ISP

connection. For more information, see

“Changing the MTU” on page 5-20

.

To change the MTU size:

1.

In the

MTU Size

field, enter a new size between 64 and 1500.

2.

Click

Apply

to save the new configuration.

Warning:

DMZ servers pose a security risk. A computer designated as the default DMZ

server loses much of the protection of the firewall and is exposed to exploits

from the Internet. If compromised, the DMZ server computer can be used to

attack other computers on your network.

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Configuring NAT Filtering

Network Address Translation (NAT) determines how the router processes inbound traffic. Secured

NAT provides a secured firewall to protect the computers on the LAN from attacks from the

Internet, but might prevent some Internet games, point-to-point applications, or multimedia

applications from functioning. Open NAT provides a much less secured firewall, but allows almost

all Internet applications to function. For more information about NAT, see

“How Your Computer

Communicates with a Remote Computer through Your Router” on page 5-2

.

To change the NAT option:

1.

In the NAT Filtering area, select either the

Secured

or the

Open

radio button.

2.

Click

Apply

to save the new configuration.

Configuring Static Routes

Static routes provide additional routing information to your router. Under usual circumstances, the

router has adequate routing information after it has been configured for Internet access, and you do

not need to configure additional static routes. You must configure static routes only for unusual

cases such as multiple routers or multiple IP subnets located on your network.

As an example of when a static route is needed, consider the following case:

•

Your primary Internet access is through a cable modem to an ISP.

•

You have an ISDN router on your home network for connecting to the company where you are

employed. This router’s address on your LAN is

1

92.168.1.100.

•

Your company’s network address is 134.177.0.0.

When you first configured your router, two implicit static routes were created. A default route was

created with your ISP as the gateway, and a second static route was created to your local network

for all 192.168.1.x addresses. With this configuration, if you attempt to access a device on the

134.177.0.0 network, your router forwards your request to the ISP. The ISP forwards your request

to the company where you are employed, and the request is likely to be denied by the company’s

firewall.

In this case you must define a static route, telling your router that 134.177.0.0 should be accessed

through the ISDN router at 192.168.1.100.

In this example:

•

The

Destination IP Address

and

IP Subnet Mask

fields specify that this static route applies

to all 134.177.x.x addresses.