Abstract
SSL VPN system depends on TUN device on Linux host. Without TUN device, it can't be deployed on Linux hosts. In order to overcome this limitation, a new kind of SSL VPN system is developed. This system is based on simulated virtual NIC based on loopback interface. With the help of simulated virtual NIC, SSL VPN client can be deployed on Linux hosts without TUN devices. Thus a Linux host without TUN devices can access the protected resources by SSL VPN. After system experiments and analysis, this kind of SSL VPN system can work well with normal network traffic. It is a new model of SSL VPN system, compared with traditional SSL VPN system.