How "Unlock Connector" feature is implemented

Hello,
In the OCPP specification there is “Unlock Connector”.
How it works ?
I suppose that upon receiving the “Unlock Connector” command through OCPP, a charger should send a command to the connector through the CAN bus. If this is correct, where can I find information on how to create such a CAN message.
One more question - this feature be implemented on all types of connectors (i.e. Type 2, CHAdeMO, Combo2, etc.) or only on particular ones ?
Thanks in advance.
Sincerely,
Pavel.