本文介绍了以ADSL宽带连接为基础的虚拟专网技术。通过此技术，企业可以在公共网络上建立虚拟的加密 通道，构筑属于自己的安全虚拟专网，从而保证企业内部的数据通过公共网络传输的安全性和保密性。并结合实际案例简单 说明通过硬件VPN防火墙设备实现加密通道的方法。

This paper introduces virtual private network technology based ADSL connection. By this technology, the enterprise can establish virtual encryption tunnel in the public network to build their own secure virtual private network, so as to ensure the security and confidentiality of enterprise data transfering through the public network. It also describe the method to achieve the encryption tunnel with VPN firewall device combined with an actual case.