Using Nat With Multiple Public Ip Addresses; Example Parameters And Scenario; Figure 41 Tutorial Example: Using Nat With Static Public Ip Addresses - ZyXEL Communications ZyWALL 2 Plus User Manual

4.2 Using NAT with Multiple Public IP Addresses

This section shows you examples of how to set up your ZyWALL if you have more than one
fixed (static) IP address from your ISP.

4.2.1 Example Parameters and Scenario

The following table shows the public IP addresses from your ISP and your ZyWALL's LAN
IP address.
Public IP Addresses
ZyWALL's LAN IP Address
The following figure shows the network you want to set up in this example.
• Assign the first public address (1.2.3.4) to the ZyWALL's WAN port.
• Map the second and third public IP addresses (1.2.3.5 and 1.2.3.6) to the web and mail
servers (192.168.1.12 and 192.168.1.13) respectively for traffic in both directions.
• Map the first public address (1.2.3.4) to outgoing traffic from other local computers.
• Map the first public address (1.2.3.4) to incoming traffic from the WAN.
• Forward FTP traffic using port 21 from the WAN to a specific local computer
(192.168.1.39).
• The last public IP address (1.2.3.7) is not mapped to any device and is reserved for future
use.

Figure 41 Tutorial Example: Using NAT with Static Public IP Addresses

To set up this network, we are going to:
1 Configure the WAN connection to use the first public IP address (1.2.3.4).
2 Configure NAT address mapping for other public IP addresses (1.2.3.5 and 1.2.3.6).
3 Configure NAT port forwarding to forward FTP traffic from the WAN to a specific
computer on your local network.
ZyWALL 2 Plus User's Guide
1.2.3.4 to 1.2.3.7
192.168.1.1
Chapter 4 Tutorials
97