User`s guide

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Configuration – Network > Virtual Private Networking (VPN) > L2TP
The Layer 2 Tunnelling Protocol (L2TP) provides a means for terminating a logical PPP
connection on a device other than the one which terminates the physical connection.
Typically, both the physical layer and logical layer PPP connections would be terminated on
the same device, a Digi Router for example.
With L2TP answering the call, the router terminates the layer 2 connection only and the PPP
frames are passed in an L2TP “tunnel” to another device which terminates the PPP
connection. This device is sometimes referred to as a Network Access Server (NAS).
Configuration – Network > Virtual Private Networking (VPN) > L2TP >
L2TP n
Act as a listener only
When checked, this checkbox causes the router to NOT actively attempt to establish an
L2TP tunnel. In this mode it will only use L2TP if the remote host requests it. When
unchecked, the router will actively try to establish an L2TP connection with the remote host.
Enable Server mode
When checked, this checkbox causes the router to act as a L2TP server.
Initiate connections to a.b.c.d
The value in this text box specifies the IP address of the remote host, i.e. the device that
will terminate the L2TP connection.
Use a.b.c.d as a backup
It is possible to specify a backup remote L2TP host server using this parameter. The text
box contains the IP address of the remote server to use.