Chapter 10 Install and System Administration for FortiOS 5.0 : PPTP and L2TP : L2TP configuration overview
  
L2TP configuration overview
To configure a FortiGate unit to act as an LNS, you perform the following tasks:
• Create an L2TP user group containing one user for each remote client.
• Enable L2TP on the FortiGate unit and specify the range of addresses that can be assigned to remote clients when they connect.
• Define firewall source and destination addresses to indicate where packets transported through the L2TP tunnel will originate and be delivered.
• Create the security policy and define the scope of permitted services between the source and destination addresses.
• Configure the remote clients.
See Also
• Authenticating L2TP clients
• Enabling L2TP and specifying an address range
• Defining firewall source and destination addresses