介绍了在Windows 平台下实现IPSec VPN 的方法。首先介绍了基于NDIS 中间层技术, 接下来介绍了使用NDIS 中间层技术实现IPSec VPN 时需要注意的几个问题如分片重组等,并提出了解决方法。该实现已经在实际中应用并取得了明显的效果。 关键词:NDIS;MTU;分片;例程 Abstract:A method of implementation of IPSec VPN in Windows platform is introduced. First of all, it introduces the NDIS intermediate technology. Then it puts forward the problems must be noticed when IPSec VPN is implemented based on NDIS, such as fragment reassembling, and it points out the way to solve the problems. The method has been implemented and taken effect. Key words: NDIS; MTU; fragment; routine