虚拟专用网（VPN）技术及WIN 2K中的实现

VPN Technology and It's Fulfillment

VPN——虚拟专用网(Virtual Private Network)是专用网络在公共网络如Internet上的扩展。VPN通过私有隧道技术在公共网上虚拟一条点到点的专线，从而达到安全的数据传输的目的。VPN能够充分利用现有的网络资源，提供经济、灵活的联网方式，为客户节省设备、管理所需的投资，降低用户的费用。基于Inernet的VPN也称为IP-VPN。

VPN is the extension of dedicated networks on public networks such as the Internet. VPN, through private tunnel techniques, virtualizes a dedicated point- to- point line for data transmission. VPN can make use of existing net resources and provide economical, flexible net connections so as to save the clients much of the investment necessary for managing equipment and reduce their expenses. The Internet-based VPN is also referred to as IP-VPN.