Resolution
The VPN client can use its real IP address if, and only if, these conditions are met:
- The head end device must be a concentrator.
- The client must be connecting through a Point to Point Tunneling Protocol (PPTP) or Layer Two Tunnel Protocol (L2TP) over IPSec tunnel.
For more information on how to use the original IP address of a remote VPN client, refer to How to configure the Cisco VPN 3000 Concentrator to allow a VPN client to use its real address (PPTP/L2TP)