Lancom Systems LCOS 3.50 - Manual (Page 307)

̈ Chapter 14: Virtual Private Networks—VPN LANCOM Reference Manual LCOS 3.50
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individual computers (RAS) or the connection of structured networks
will be covered subsequently.
14.5.1 VPN tunnel: Connections between VPN gateways
Virtual Private Networks (VPNs) are used to interconnect local networks over
the Internet. This involves the routing of the private LAN IP addresses via an
Internet connection between two gateways with public IP addresses.
For the secure routing of private IP addresses over the Internet, a VPN
connection, also known as a VPN tunnel, is established between the two
LANs.
The VPN tunnel has two important tasks:
̈ To shield the transported data from unauthorized access
̈ To route private IP addresses via an Internet connection that can normally
only be used to route public IP addresses.
The VPN connection between the two gateways is defined by the following
parameters:
̈ The end-points of the tunnel, the VPN gateways, each of which are
accessible via public IP addresses (static or dynamic)
̈ The IP connection between the two gateways
̈ The private IP address range that are to be routed between the VPN
gateways
̈ Setting relevant to security, such as passwords, IPSec keys etc. to shield
the VPN tunnel
This information is contained in the so-called VPN rules.
VPN tunnel with IPSec
encryption
IP network: 10.1.0.0
Net mask: 255.255.0.0 IP network: 10.2.0.0
Net mask: 255.255.0.0
IP connection
IP address:
80.146.81.251 IP address:
217.213.77.120