Specifications

Virtual Private Network (VPN)
AVM Access Server – 5 AVM Access Server Concepts and Functional Principles 81
5.7 Virtual Private Network (VPN)
The AVM Access Server allows you to set up Virtual Private Network
(VPN) connections. VPN connections are an economical way to connect
both remote networks and single remote PCs to the company LAN. Un-
til recently, remote systems were usually interconnected using direct
dial-up or leased line connections over public telecommunication net-
works, such as ISDN or GSM. The costs for such direct connections
increase with the distance between the remote systems. Systems sep-
arated by long distances can be economically linked by VPN connec-
tions.
VPNs in General
A remote network is connected to the local network by a VPN link trans-
ported over the Internet.
Example: a VPN connection over the Internet
The private connection carried over the public Internet between the
two communicating parties is called a tunnel. The two networks ex-
change data through this tunnel. The two LANs do not share a physical
network connection: the shared network is a virtual one. The virtual
network is a higher-order data structure that uses the existing public
infrastructure of the Internet for data transport. The other interfaces
and applications of the two connected systems are not affected by the
VPN link. The connection is economical because both sites only incur
charges for a connection to an Internet Service Provider.
Local Network
Internet
Tunnel
Remote Network
AVM Access Server AVM Access Server