Communication Modes

Devices connect to the IoT platform and communicate with an application through the platform. The following figure shows the communication between devices, application, and the platform.

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Device Sending Data to the Platform

A device can connect to and communicate with the platform. Data can be sent to the platform through the following APIs:

API for reporting a message. When a device cannot report data in the property format defined in the product model, it can use this API to report custom data to the platform, which then forwards the data to the application or other Huawei Cloud services for storage and processing.
API for reporting device properties, which is used by a device to report properties in the format defined in the product model to the platform.
API for batch reporting device properties, which is used by a gateway to report properties of multiple devices in a batch to the platform.
API for reporting an event, which is used by a device to report event data in the format defined in the product profile to the platform.

Application Delivering Commands to Devices

An application can use the following APIs to send commands to a device that has been connected to the platform:

API for delivering a message, which is used by the platform to deliver data in a custom format to a device.
API for setting device properties. The product model of a device defines the properties that the platform can set for the device. An application can use this API to modify the properties of a device.
API for querying device properties, which is used by an application to query properties of a device in real time.
API for delivering a command, which is used by an application to deliver commands in the format defined in the product model to a device.
API for delivering an event, which is used by an application to deliver an event in the format defined in the product model to a device.