IPSec协议是VPN的实现方式之一。该文简要介绍了IPSec协议，分析TI inux2．4内核的NetnItcr框架和／pr c文件系统，提出T -种在Linux中实现VPN网关的方法-IPSec protocol is a way to achieve one of the VPN. This article briefly introduces the IPSec protocol, analysis of TI inux2.4 kernel NetnItcr framework and/