The Research and Implementation of the VPN Gateway Based on SSL

VPN technology is the use of the knowledge of cryptography in the open and public network to establish a virtual private network. IPSec VPN and SSL VPN are two kinds of VPN technology and products used in most cases currently. IPSec VPN operates at the network layer, SSL VPN works in secure sockets layer. SSL VPN uses a series of cryptographic techniques, including symmetric encryption, asymmetric encryption, digital signatures, digital certificates, as well as message digest algorithm. This article analyzes the principle of VPN technology and the SSL protocol. I proposed a solution of VPN gateway based on the SSL protocol.