When a user installs a serial cable on an active MM, the serial terminal of the customer is presented with a Serial Console menu from which they can choose actions from. The action list is populated based on available components.
Endpoint (components) must support authentication, otherwise endpoint is at risk or unauthorized users gaining access to device. This risk is no different than a user plugging a cable directly into the external serial port of the device as the MM only extends the device serial port to a common location at the back of the chassis. Each endpoint in the chassis that supports serial access authenticates and authorizes the user.