How can IoT systems control be exclusively set to one of auto, manual?
It should be possible to set the system state of an IoT System to manual or auto in an explicit manner. While in manual mode the auto control must not interfere and vice versa.
A control latch is defined which preserves the control mode. The control latch has a secure access to avoid malicious or accidental overwrite.
Upon any change in the monitored IoT System, before running the auto action the system checks the state of control latch. The auto-action routine is invoked only if the state of control-latch is auto, else no auto-action is invoked. Similarly, when a manual action is triggered the action is performed only if the state is manual.
Figure 3 Exclusive manual / auto control switch
System in maintenance mode: Example powerline, lift.