Industry Cellular Gateway
5.1.3 L2TP
Layer 2 Tunneling Protocol (L2TP) is a tunneling protocol used to support virtual private networks (VPNs) or as
part of the delivery of services by ISPs. It does not provide any encryption or confidentiality by itself. Rather, it
relies on an encryption protocol that it passes within the tunnel to provide privacy. This Gateway can behave
as a L2TP server and a L2TP client both at the same time.
L2TP Server:
It must have a static IP or a FQDN for clients to create L2TP tunnels. It also maintains “User
Account list” (user name/ password) for client login authentication; There is a virtual IP pool to assign virtual IP
to each connected L2TP client.
L2TP Client
: It can be mobile users or gateways in remote offices with dynamic IP. To setup tunnel, it should
get “user name”, “password” and server’s global IP. In addition, it is required to identify the operation mode
for each tunnel as main connection, failover for another tunnel, or load balance tunnel to increase overall
bandwidth. It needs to decide “Default Gateway” or “Remote Subnet” for packet flow. Moreover, you can also
define what kind of traffics will pass through the L2TP tunnel in the “Default Gateway / Remote Subnet”
parameter.
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