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L2TP VPN

This feature may not be available on all platforms. Please check your system's actual page if your device delivers this feature.

L2TP (Layer Two Tunneling Protocol) is a VPDN technique that allows dial-up users to launch VPN connection from L2TP clients or L2TP access concentrators (LAC), and connect to a L2TP network server (LNS) via PPP. After the connection has been established successfully, LNS will assign IP addresses to legal users and permit them to access the private network.

The device acts as a LNS in the L2TP tunnel network. The device accepts connections from L2TP clients or LACs, implements authentication and authorization, and assigns IP addresses, DNS server addresses and WINS server addresses to legal users.

L2TP does not encrypt the data transmitted through the tunnel, so it cannot assure security during the transmission. You can use L2TP in combination with IPsec, and encrypt data by IPSec, thus assuring the security during the data transmitted through the L2TP tunnel.

Configuring an L2TP VPN

To create an L2TP VPN instance, take the following steps:

  1. Select Network > VPN > L2TP VPN.
  2. In the L2TP VPN page, click New.
  3. If necessary, click Advanced Configuration to configure the advanced functions.
  4. Click Done to save the settings.

Configuring an L2TP VPN Address Pool

LNS assigns the IP addresses in the address pool to users. After the client has established a connection to LNS successfully, LNS will choose an IP address along with other related parameters (such as DNS server address, WINS server address, etc) from the address pool, and assign them to the client.

L2TP provides fixed IP addresses by creating and implementing IP binding rules.

  • The static IP binding rule binds the client user to a fixed IP address in the address pool. Once the client has established a connection successfully, system will assign the binding IP to the client.
  • The IP-role binding rule binds the role to a specific IP range in the address pool. Once the client has established a connection successfully, system will assign an IP address within the IP range to the client.

When LNS is allocating IP addresses in the address pool, system will check the IP binding rule and determine how to assign IP addresses for the client based on the specific checking order below:

The IP addresses defined in the static IP binding rule and IP-role binding rule should not be overlapped.

To create an address pool, take the following steps:

  1. Select Network > VPN > L2TP VPN.
  2. At the top-right corner, click Address Pool.
  3. In the pop-up window, click New.
  4. Click OK to save the settings.

Viewing L2TP VPN Online Users

To view the L2TP VPN online users, take the following steps:

  1. Select Network > VPN > L2TP VPN.
  2. Select an L2TP VPN instance.
  3. View the detailed information of the online users in the table.

    Option Description
    Name Displays the name of L2TP VPN.
    Login Time Displays the login time of the L2TP VPN online user.
    Public IP Displays the public IP of the L2TP VPN online user.
    Private IP Displays the private IP of the L2TP VPN online user.
    Operation Displays the executable operation of the L2TP VPN online user.