OpenVPN is a cross-platform networking solution that establishes secure virtual private network connections by wrapping data traffic within encrypted tunnels. It functions as a server-side application that authenticates remote endpoints and routes encrypted traffic to provide access to private network resources across untrusted public networks.
The software utilizes standard cryptographic protocols to perform mutual authentication and key exchange over a dedicated control channel. It verifies the identity of remote systems through certificate-based authentication, ensuring that only trusted endpoints can establish a connection. By processing network traffic within the application layer and utilizing virtual network interfaces, it presents encrypted data as standard local network packets to the operating system.
The project supports a range of networking configurations, including secure remote access for individual devices, site-to-site infrastructure linking, and zero trust network access models. It maintains persistent session metadata to allow for reconnection without requiring a full re-authentication handshake, while protecting data integrity through keyed hash authentication for every packet.
