Configuring the NAT server in Win 2003

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This article describes how to configure a network address translation (NAT) server by using Windows Server 2003来. The Windows Server 2003 Routing and Remote Access service includes the NAT routing protocol. If you install and configure the NAT routing protocol on a server that is running Routing and Remote Access, internal network clients that use the private Internet Protocol (IP) address can access the Internet through the external interface of the NAT server.

How to configure Routing and Remote Access NAT servers

When an internal network client sends a request to connect to the Internet, the NAT protocol driver intercepts the request and forwards it to the destination Internet server. All requests look like external IP addresses from the NAT server. This hides your internal IP address configuration.

To configure the Routing and Remote Access NAT server:

From the Administrative Tools menu, select Routing and Remote Access.

In the Routing and Remote Access MMC, expand your server name, where the server name is the name of the server you want to configure, and then expand the IP route in the left pane.

Select General, and then select New routing Protocol.

Click the nat/Basic Firewall check box to select it, and then point to OK.

Right-click the nat/Basic Firewall in the left pane, and then click New Interface.

Click the interface that represents the internal network interface, and then click OK.

In the network address translation attribute, click Private interface to connect to private network, and then click OK.

Right-click the nat/Basic Firewall in the left pane, and then point to the new interface.

Click the interface that represents the external network interface, and then point to OK.

In the network address translation attribute, click Public interface to connect to the Internet.

Click the Enable NAT on this interface check box to select it and point to OK.

The NAT server can automatically assign IP addresses to internal network clients. You may need to use this feature if you do not have a DHCP server that has address information assigned to clients on the internal network.

How to configure the Routing and Remote Access NAT server to assign IP addresses and perform proxy DNS queries the NAT server can also perform domain Name System (DNS) queries on behalf of the NAT client. The Routing and Remote access NAT server resolves the Internet host name that is included in the client request, and then forwards the IP address to the client.

To configure the Routing and Remote Access NAT server to assign IP addresses and perform proxy DNS queries on behalf of internal network clients, follow these steps:

Right-click the nat/Basic Firewall in the left pane, and then click Properties.

Click the Address Assignment tab, and then click the automatically assign IP addresses using DHCP check box to select it.

In the IP Address box, type the network ID.

In the Mask box, type the subnet mask.

Select the Name Resolution tab, and then click the Use domain Name System (DNS) Client check box to select it.

If you are using a demand-dial interface to connect to the Internet, click to select the Connect to public network when the name needs to be resolved check box.

In the Demand-dial interface box, select the interface you want to dial.

Select the application, and then click OK.

Note: After you complete these basic configuration steps, the internal network client can access servers on the Internet.

How to configure a Windows Server 2003-based computer to use a NAT server

Click Start, point to Control Panel, point to Network Connection, and then click Local Area Connection.

Click Properties.

Click Internet Protocol (TCP/IP).

Click Properties.

In the Default gateway box, type the internal IP address of the NAT server.

Note: If the computer receives its IP address from the Dynamic Host Configuration Protocol (DHCP) server, click Advanced, click the IP Settings tab, click Add under the Gateway, type the internal IP address of the NAT server, click Add, click OK, and then proceed to step 6th.

Click OK, click OK, and then click Close.