OpenVPN - Wikipedia

Two-Factor Authentication for OpenVPN | Duo Security Apr 06, 2020 OpenVPN FAQs - UntangleWiki May 19, 2020 OpenVPN Connect 3.2.2 for Android - Download

Pritunl Client - Open Source OpenVPN Client

Compared to OpenVPN 2.3 this is a major update with a large number of new features, improvements and fixes. Some of the major features are AEAD (GCM) cipher and Elliptic Curve DH key exchange support, improved IPv4/IPv6 dual stack support and more seamless connection migration when client's IP address changes (Peer-ID).

OpenVPN - Wikipedia

Jan 28, 2015 openVPN - CAcert Wiki