Microsoft® Windows® 2000 Security Handbook

What's a VPN and Why Would You Use One?

Probably one of the most misused terms in the computer industry today is VPN. It seems as though every vendor has a VPN to sell you, and many times one vendor's "VPN" can seem to be the exact opposite of another's. For example, not too long ago one of the major telecommunications vendors offered a VPN service that consisted of a private frame relay network that users could dial in to and then, utilizing the frame relay network, connect to the businesses network. It involved no encryption, and the only true security provided by the solution was whatever mechanism the customer provided at the frame relays point of entry to the corporate network. Another VPN vendor will try to sell you a dedicated hardware ...