OpenVPN is a robust and highly configurable VPN (Virtual Private Network) daemon which can be used to securely link two or more private networks using an encrypted tunnel over the Internet. OpenVPN's principal strengths include wide cross-platform portability, excellent stability, support for dynamic IP addresses and NAT, adaptive link compression, single TCP/UDP port usage, a modular design that offloads most crypto tasks to the OpenSSL library, and relatively easy installation that in most cases doesn't require a special kernel module.
OpenVPN Auth Passwd is a plugin that authenticates OpenVPN users using the local passwd or shadow files, using a privilege separation model. The authentication method must be defined in the Makefile prior to the compilation of the plugin. On shadowed systems it uses the functions provided in the shadow suite and, on other systems, the getpwnam(3) function to verify the username/password.
GADMIN-OpenVPN-Server is an easy to use GTK+ interface for the OpenVPN server in bridge mode. It allows generation of five signed certificates and keys, including HMAC-Firewall and user authentications. Bridge mode enables SAMBA browsing and printing across physically separated networks and or full-blown road warrior client capabilities.
OpenVPN Web Certificate Manager is a configuration, certification, and management tool for OpenVPN using a Web-based interface. It shows the status of multiple OpenVPN servers running on the same system; for each, it shows the VPN connections and OpenVPN/OpenSSL configuration. Moreover, it provides client certificate management.