基于PPTP-SSH隧道网关的VPN系统研究与实现

Research and implementation of VPN system based on PPTP-SSH tunnel gateway

文中提出了一种基于PPTP-SSH隧道网关的VPN系统。该系统中客户端通过PPTP协议接入VPN系统,进入系统的客户端数据包通过iptables重定向或UDP到TCP的转换进入透明SOCKS代理,将原有的TCP连接转换为SOCKS连接,最后通过SSH隧道访问内部网络。本系统支持包括移动终端设备在内的多种客户端设备,支持穿越NAT及访问IPv6网络。实际应用表明,该系统很好地满足了VPN系统的易用性和灵活性的要求。

This paper presents a VPN system based on PPTP - SSH tunnel gateway. In this system, the client accesses VPN system by the PPTP protocol, and client packages which have entered the system through the iptables redirection or UDP to TCP conversion gain access to transparent SOCKS proxy. The original TCP connection is converted to SOCKS connection and enables it to access the internal network by SSH tunnel. The system supports a variety of clients, including mobile devices, and also supports NAT and IPv6 internal network. The implementation shows that this system has a good flexibility and is ease of use .