Setting Up An L2Tp Server - D-Link DFL-1660 User Manual

9.5.2. L2TP Servers
arguably offers better security than PPTP. Unlike PPTP, it is possible to set up multiple virtual
networks across a single tunnel. Because it is IPsec based, L2TP requires NAT traversal (NAT-T) to
be implemented on the LNS side of the tunnel.
Example 9.11. Setting up an L2TP server
This example shows how to setup a L2TP Network Server. The example assumes that you have created some IP
address objects. You will have to specify the IP address of the L2TP server interface, an outer IP address (that
the L2TP server should listen to) and an IP pool that the L2TP server will use to give out IP addresses to the
clients from.
Command-Line Interface
gw-world:/> add Interface L2TPServer MyL2TPServer
Web Interface
1. Go to: Interfaces > L2TP Servers > Add > L2TPServer
2. Enter a suitable name for the L2TP Server, for example MyL2TPServer
3. Now enter:
• Inner IP Address: ip_l2tp
• Tunnel Protocol: L2TP
• Outer Interface Filter: any
• Outer Server IP: wan_ip
4. Under the PPP Parameters tab, select L2TP_Pool in the IP Pool control.
5. Under the Add Route tab, select all_nets in the Allowed Networks control.
6. Click OK
Use User Authentication Rules is enabled as default. To be able to authenticate users using the PPTP tunnel, it
is necessary to configure NetDefendOS Authentication Rules but that is not covered in this example.
Example 9.12. Setting up an L2TP Tunnel Over IPsec
This example shows how to setup a fully working L2TP Tunnel based on IPsec encryption and will cover many
parts of basic VPN configuration.
Before starting, it is necessary to configure some address objects, for example the network that is going to be
assigned to the L2TP clients. Proposal lists and PSK are needed as well. Here we will use the objects created in
previous examples.
To be able to authenticate the users using the L2TP tunnel a local user database will be used.
Note: All DHCP special parameters are not sent to clients
When DHCP is configured on an L2TP/IPsec interface to hand out client IPs,
NetDefendOS does not return all the DHCP special parameters. This can be the
source of issues with Windows based L2TP clients running under Vista or Windows 7.
ServerIP=ip_l2tp
Interface=any
IP=wan_ip
IPPool=L2TP_Pool
TunnelProtocol=L2TP
AllowedRoutes=all-nets
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Chapter 9. VPN