A VPN Framework through Multi-layer Tunnels based on OpenSSH

This paper details how to setup and test the new tunneling features of OpenSSH to establish an enhanced SSH Layer 3 VPN between three computers in a Wide Area Network (WAN) environment. The OpenSSH security feature will be explored to provide secure tunneling and different authentication methods. Using OpenSSH to built VPN will cater for security by encrypting the data transmitted across the public network to private networks. OpenSSH VPN is said to have limitations with numerous clients and therefore it is advisable to use OpenVPN when dealing with more than one clients. To the best knowledge of the authors, this is the first reported successful implementation of a wide-area network VPN using OpenSSH tunnels with multiple clients. This proof-of-concept positions OpenSSH therefore as a potential alternative to the more conventional OpenVPN.