Correct Answer: IoT Hub stores the messages in a queue up to the configured Time-To-Live (TTL) limit and delivers them when the device reconnects
IoT Hub maintains a C2D queue for each registered device. When a device is offline, messages sent to it are stored in the queue. They remain there until the message's Time-To-Live ...
Correct Answer
IoT Hub stores the messages in a queue up to the configured Time-To-Live (TTL) limit and delivers them when the device reconnects
Why This Answer Is Correct
IoT Hub maintains a C2D queue for each registered device. When a device is offline, messages sent to it are stored in the queue. They remain there until the message's Time-To-Live (TTL) expires (default is 1 hour, configurable up to 48 hours), or until the device reconnects and retrieves them.
This question evaluates your knowledge of Azure IoT Hub — a core concept tested in Microsoft Certified: Azure IoT Developer Specialty (AZ-220). Understanding Azure IoT Hub is essential for designing scalable, secure, and cost-effective cloud architectures. Mastery of this topic will help you answer scenario-based questions confidently on exam day.
You are building an IoT solution where 50,000 devices must send telemetry every 30 seconds. Your IoT Hub is receiving messages but you are hitting throttling errors. Which action should you take first?
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Your IoT devices need to upload 50 MB diagnostic log files to the cloud periodically. Using IoT Hub device-to-cloud messages is not suitable due to the 256 KB size limit. What is the correct IoT Hub capability for this?