Cisco Cisco ISA550W Integrated Security Appliance Quick Setup Guide

© 2012 Cisco Systems, Inc. All rights reserved.

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Step 2.

Select the PAT IP address for each WAN port. 

In this example, WAN1 and WAN2 are set to 

Auto, which automatically uses the IP address of 

the WAN port as the translated IP address.

If you select 

Manual, choose a single public IP address or a network address as the translated 

IP address. If the address object is not available, choose 

Create a new address to create a 

new address object. 

Step 3.

Choose one of the following to translate multiple private IP addresses of a VLAN to one or 
more mapped IP addresses.

–

Enable WAN1: Translates all IP addresses of the selected VLAN into the public IP address 
specified on the WAN1 port.

–

Enable WAN2: Translates all IP addresses of the selected VLAN into the public IP address 
specified on the WAN2 port.

–

VLAN IP Address: Subnet IP address and netmask of the selected VLAN.

Step 4.

Click 

Save when you are finished.

This section describes the different type of NAT methods that you can configure by using Advanced NAT. 
It includes the following sections:

You can configure up to 16 advanced NAT rules on the ISA500.

Forwarding Traffic from Non-Native VLANs to the Internet
Scenario 1: To allow hosts that are not in local VLANs of the ISA500 to access the Internet. In this 
scenario, another router is located behind the ISA500 in a Dual WAN configuration. To accomplish this 
task you will need to create two Advanced NAT rules on the ISA500.