Firmware 2_7_0 (D6x) is recommended and D80 (1_9_0). Versions between 2_2_1_1 and 2_6_6 support a series of deprecated OpenVPN configuration parameters that are not supported going forward and will be removed in a future firmware release.
OpenVPN connectivity is supported by models D60, D62, D65, and D65D80. Models D40, D45, D50, and D70 , and D80 do not support OpenVPN connectivity.
client dev tun proto udp remote server.example.com 1194 resolv-retry infinite nobind ns-cert-type server verb 3 <ca> -----BEGIN CERTIFICATE----- sFA... -----END CERTIFICATE----- </ca> <cert> -----BEGIN CERTIFICATE----- MII... -----END CERTIFICATE----- </cert> <key> -----BEGIN PRIVATE KEY----- MII... -----END PRIVATE KEY----- </key>
Digium D6x phones support the following Control Channel TLS Ciphers:
Model D80 phones may support a different set of Control Channel TLS Ciphers.
Versions of firmware prior to 2.3.9 also supported the following, additional ciphers:
AECDH-RC4-SHA, AECDH-DES-CBC3-SHA, AECDH-AES128-SHA, AECDH-AES256-SHA
Digium D6x phones support the following Data Channel Ciphers:
RC2-CBC, RC2-40-CBC, RC2-64-CBC
Model D80 phones may support a different set of Data Channel Ciphers.
The use of ciphers may impact the performance of the phone. Normal operation with the listed ciphers has been tested, but it is conceivable that certain combinations of ciphers, transports, RTP encryption, numbers of calls, codecs, audio paths, subscriptions, applications, etc., could result in audio degradation. If audio degradation is experienced, use alternate ciphers, transports, RTP, codecs, subscriptions, etc.