VPN software applications include clients, servers and utility programs. VPN software technology enables private communications over wireless / computer networks via a method called "tunneling." The popular VPN software applications listed below are readily available for free download on the Internet.
Hamachi is free VPN software that uses a mediation server to establish peer-to-peer connections over UDP.
OpenVPN is SSL-based open source VPN software. OpenVPN runs on Windows, Linux and Mac OS X operating systems.
The Cisco VPN client software supports IPSec connections to Cisco VPN concentrators. This VPN software application runs on Windows, Linux and Mac OS X.
The free Tinc VPN software enables virtual private networking via low-level daemon / network device configuration. Designed originally for Linux / Unix networks, Tinc also works on Windows computers.
FreeS/WAN is an IPSec VPN software solution for Linux networks. Active development of FreeS/WAN has stopped, making this solution of interest mainly to students and researchers.