Used to define OpenVPN security details.
OpenVPN supports three authentication/encryption modes.
Complete the key information by entering the information into the following fields:
Secret: the file containing the pre-shared key (static mode only).
Certificate: the file containing the local X509 certificate signed by certificate authority (SSL/TLS mode only).
Private Key: the local private key file (SSL/TLS mode only).
CA: the certificate authority file (SSL/TLS mode only).
TLS auth: additional and option tls authentication layer (SSL/TLS mode only). TLS authentication is an optional layer of security and is not required for SSL/TLS.