The VPN has attracted the attention of many organizations looking to both expand their networking capabilities and reduce their costs. The VPN can be found in workplaces and homes, where they allow employees to safely log into company networks. Telecommuters and those who travel often find a VPN a more convenient way to stay "plugged in" to the corporate intranet.

A VPN supplies network connectivity over a possibly long physical distance. In this respect, a VPN is a form of a Wide Area Network (WAN).  The key feature of a VPN, however, is its ability to use public networks like the Internet rather than rely on private leased lines. VPN technologies implement restricted-access networks that utilize the same cabling and routers as a public network, and they do so without sacrificing features or basic security.

A VPN supports at least three different modes of use:

• Remote access client connections
• LAN-to-LAN internetworking
• Controlled access within an intranet

Using a VPN can have a major impact on a company by increasing sales. Product or sales development can be accelerated.

In recent years, many organizations have increased the mobility of their workers by allowing more employees to telecommute.  Employees also continue to travel and face a growing need to stay connected to their company networks.

A VPN can be set up to support remote, protected access to the corporate home offices over the Internet. An Internet VPN solution uses a client/server design works as follows:

1. A remote host (client) wanting to log into the company network first connects to any public Internet connection.
2. Next, the remote host initiates a VPN connection to the company VPN firewall. This connection is made via a VPN client installed on the remote host.  This is built into the Windows Professional operating systems.
3. Once the connection has been established, the remote client can communicate with the internal company systems over the Internet just as if it were in the physical office.