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About Virtual Private Networking

Note: This topic applies to the Leeds Release.

Note: A Unified Threat Management serial is required to configure VPNs. For more information, contact your Smoothwall representative.

A virtual private network (VPN), in the broadest sense, is a network route, referred to as a tunnel, between computer networks, or individual computers, across a public network. The public network, in most cases, is the Internet. Typically, a VPN replaces a leased line or other circuit which is used to link networks together over some geographic distance.

In a similar way to how a VPN can replace leased line circuits used to route networks together, a VPN can also replace Remote Access Server (RAS) phone or ISDN lines. These types of connections are usually referred to as roadwarriors.

There are several technologies which implement VPNs. The most commonly deployed VPN protocol is called IPSec (IP Security), and is a well established and open Internet standard.

VPNs are mostly used to link multiple branch office networks together, site-to-site VPNs, or to connect mobile and home users to their office network.

The network route between a site-to-site or roadwarrior VPN is provided by a VPN tunnel. Tunnels can be formed between two VPN gateways. All data traversing the tunnel is encrypted, thus making the tunnel and its content unintelligible and therefore private to the outside world.