Handles SASL authentication with Cassandra servers. Each time a new connection is created and the server requires authentication, a new instance of this class will be created by the corresponding.
Evaluates a challenge received from the Server. Generally, this method should callback with no error and no additional params when authentication is complete from the client perspective.
Obtain an initial response token for initializing the SASL handshake.
Called when authentication is successful with the last information optionally sent by the server.