Lancom Systems LCOS 3.50 Manuel D’Utilisation
Chapter 14: Virtual Private Networks—VPN
LANCOM Reference Manual LCOS 3.50
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14 Virtual Private Networks—VPN
14.1
What does VPN offer?
A VPN (Virtual Private Network can be used to set up cost-effective, public IP
networks, for example via the Internet.
networks, for example via the Internet.
While this may sound unspectacular at first, in practice it has profound effects.
To illustrate this, let's first look at a typical corporate network without VPN
technology. In the second step, we will see how this network can be optimized
by the deployment of VPN.
To illustrate this, let's first look at a typical corporate network without VPN
technology. In the second step, we will see how this network can be optimized
by the deployment of VPN.
Conventional network infrastructure
First, let's have a look at a typical network structure that can be found in this
form or similar forms in many companies:
form or similar forms in many companies:
The corporate network is based on the internal network (LAN) in the
headquarters. This LAN is connected to the outside world in three ways:
headquarters. This LAN is connected to the outside world in three ways:
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A subsidiary is connected to the LAN, typically using a leased line.
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PCs dial into the central network via modem or ISDN connections (Remote
Access Service – RAS).
Access Service – RAS).
Headquarters
Computers
using remote
access, e.g.
home working
Internet
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LAN
LAN
Branch office
ISDN
ISDN
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