The use of the Internet and Internet-type software for subsytems of computing for private organizations and individuals. Companies are storing key forms and documents on web sites inside their operations, making it easy for employees to find information using standard web browsers, not special-purpose database programs. Most intranets use the "free" connections of the Internet, and turn the Internet into an intranet with passwords or other access barriers to documents and databases. Combinations of free Internet lines connected with leased (usually from telephone companies) private nodes are termed "virtual private networks" or VPN . A VPN functionality of a dedicated line, but which is really like a private
network within a public one, because it is still controlled by a telephone company. VPN's use encryption and other security mechanisms to ensure that only authorized users can access the network and that the data cannot be intercepted. Some security mechanisms exist that are not available on intranets. The finer points of VPN networking is discussed by in a very long article by Mike Fratto in "VPNs Across Multiple Sites," Network Computing, July 1, 1998, 38-70.(See also TCP/IP , WAN , LAN , and Extranet .)