Frost-Free Valve Control
Question
You are operating the IoT infrastructure of a chemical plant where devices are used to ensure that critical valves built-in outdoor pipelines are free from frost.
In normal weather conditions, the devices operate as planned, but in unexpectedly and extremely cold weather, the extra heater of some valves must be turned on remotely, with immediate acknowledgment from the device.
Which of the following solutions should you use?
Answers
Explanations
Click on the arrows to vote for the correct answer
A. B. C. D.Correct Answer: A.
Option A is CORRECT because, with IoT hub's routing capability, you can forward incoming messages to other Azure services as custom endpoints, like Blob Storage or Service Bus.
Enrichment of message also can be applied as part of the routing.
Option B is incorrect Azure Service Bus (both topics and queues) are possible custom endpoints for IoT Hub, hence they are valid targets in message routing.
References:
In the given scenario, the chemical plant uses IoT devices to monitor the valves built-in outdoor pipelines, and ensure they are free from frost. In normal weather conditions, the devices operate as planned, but in extremely cold weather, an extra heater may need to be turned on remotely with immediate acknowledgment from the device. To implement this solution, the following options are provided:
A. Send a C2D message to the heater: This solution involves sending a cloud-to-device (C2D) message to the extra heater to turn it on. While this is a viable solution, it is not the best approach as it may not provide immediate acknowledgment from the device, as required in the scenario. Additionally, C2D messages are not guaranteed to be received by the device.
B. Set the extraHeating desired property of the device twin “On”: This solution involves setting the desired property of the device twin to turn on the extra heater. The device twin is a digital representation of the physical device, and desired properties are used to update the device's configuration. This solution is more suitable as it allows for immediate acknowledgment from the device as it sends a confirmation message to the cloud when the desired property is updated.
C. Set the extraHeating tag of the device twin “On”: This solution involves setting a tag on the device twin to turn on the extra heater. Tags are used to add metadata to the device twin and can be used to query and filter devices. However, tags are not used to update the device configuration and do not provide immediate acknowledgment from the device.
D. Invoke the extraHeating method of the device: This solution involves invoking a method on the device to turn on the extra heater. Methods are used to trigger actions on the device, and this solution could work. However, it may not provide immediate acknowledgment from the device as the method may take some time to execute, and it may not be guaranteed to be received by the device.
Based on the scenario, the best solution is option B, which involves setting the extraHeating desired property of the device twin “On.” This solution allows for immediate acknowledgment from the device as it sends a confirmation message to the cloud when the desired property is updated. Additionally, using desired properties to update the device configuration is a common approach in IoT solutions.
