Draytek Vigor2120 series User Manual page 274

Dial-Out Settings
Vigor2120 Series User's Guide
through the router.

Block – This is default setting. Click this button to let
multicast packets be blocked by the router.
Call Direction - Specify the allowed call direction of this
LAN-to-LAN profile.

Both:-initiator/responder

Dial-Out- initiator only

Dial-In- responder only.
Always On-Check to enable router always keep VPN
connection.
Idle Timeout: The default value is 300 seconds. If the
connection has been idled over the value, the router will
drop the connection.
Enable PING to keep alive - This function is to help the
router to determine the status of IPsec VPN connection,
especially useful in the case of abnormal VPN IPsec tunnel
disruption. For details, please refer to the note below.
Check to enable the transmission of PING packets to a
specified IP address.
Enable PING to keep alive is used to handle abnormal
IPsec VPN connection disruption. It will help to provide the
state of a VPN connection for router's judgment of redial.
Normally, if any one of VPN peers wants to disconnect the
connection, it should follow a serial of packet exchange
procedure to inform each other. However, if the remote peer
disconnect without notice, Vigor router will by no where to
know this situation. To resolve this dilemma, by
continuously sending PING packets to the remote host, the
Vigor router can know the true existence of this VPN
connection and react accordingly. This is independent of
DPD (dead peer detection).
PING to the IP - Enter the IP address of the remote host
that located at the other-end of the VPN tunnel.
Type of Server I am calling –
PPTP - Build a PPTP VPN connection to the server
through the Internet. You should set the identity like User
Name and Password below for the authentication of remote
server.
IPsec Tunnel - Build an IPsec VPN connection to the
server through Internet.
L2TP with IPsec Policy - Build a L2TP VPN connection
through the Internet. You can select to use L2TP alone or
with IPsec. Select from below:

None: Do not apply the IPsec policy. Accordingly, the
VPN connection employed the L2TP without IPsec
policy can be viewed as one pure L2TP connection.

Nice to Have: Apply the IPsec policy first, if it is
applicable during negotiation. Otherwise, the dial-out
VPN connection becomes one pure L2TP connection.

Must: Specify the IPsec policy to be definitely
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