White Paper Abstract:
This document shows how to configure a Network Address Translation Traversal (NAT-T) between Cisco VPN Clients located behind a Port Address Translation (PAT)/NAT device and a remote Cisco VPN Concentrator. NAT-T can be used between VPN Clients and a VPN Concentrator, or between concentrators behind a NAT/PAT device. NAT-T can also be used when connecting to a Cisco router running Cisco IOS® Software and PIX Firewall; however, these configurations are not discussed in this document.