Source NAT

Network Address Translation (NAT) is the process that enables a single device, such as a router or firewall, to act as an agent between the internet or public network and a local or private network. This agent acts in real-time to translate the source or destination IP address of a client or server on the network interface. Source IP translation enables a single, public address to represent a significantly larger number of private addresses. Destination IP translation enables the firewall to translate a public, destination address to a private address. So we don't have to configure a real public IP address for the server deployed in a private network.

NAT can be subdivided into two types:

• Source NAT (SNAT)

• Destination NAT (DNAT)

This section is about SNAT. Three NAT working modes are supported: static SNAT, dynamic SNAT, and central SNAT. For information about DNAT, see Destination NAT.

The following topics provide instructions on configuring policies with source NAT:

• Static SNAT

• Dynamic SNAT

• Central SNAT

• Configuring an IPv6 SNAT policy

• SNAT policies with virtual wire pairs

• Configuring PCP port mapping with SNAT and DNAT