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LANCOM 7111 VPN – LANCOM 8011 VPN
Chapter 1: Introduction
Connecting a LAN to the Internet does not technically differ from coupling two LANs. The only difference is that it is not just a handful of computers behind the Internet provider's router. Instead, it is the net of the networks - the public Internet.
1.3.1Bridgehead to the WAN
All routers have at least two connections: at least one for the LAN
at least one for WAN connections
In addition to LAN connectivity (10/100 Mbps Ethernet), several models also offer an integrated switch. For the connecting to the WAN, the routers use ISDN, xDSL/cable or ADSL connectors. Several devices contain additionally a wireless network card and can thus integrate also stations of WLANs (Wireless LANs) into the routing.
The router's task is to transfer data from the local network to the target net- work via a suitable WAN connection. Data is also transferred from the WAN to the desired recipients in the LAN.
1.3.2Areas of deployment for routers
Not possible with all LANCOM devices.
Routers are mainly used for the following applications:
Internet access for a LAN (e.g. via DSL or ISDN)
The Internet consists of countless large and small networks that are inter- connected into the world's largest WAN via routers. The router links all the workstation computers on your local area network to the global Internet. Security functions such as IP masquerading protect your LAN against unauthorized access from outside.
LAN to LAN coupling (via VPN or ISDN)
LAN to LAN coupling links individual LANs to form one large network, even if this means crossing continents. A typical example: A branch office is to be connected to the LAN of the headquarters. In principle, you can connect LANs in two ways:
The fastest and most economical LAN to LAN links are possible with VPN (Virtual Private Network) technology, as VPN uses the Internet as the basis for its communications. The fast xDSL connection of the router comes into its own here. The precondition: a VPN gateway with
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