IoT Platform (OceanConnect / IoTDA) and Device Management
What the exam tests
OceanConnect/IoTDA concepts: product and device models, device shadow, commands, OTA, rules, and APIs.
Core rules
- A product defines a device model: service, properties, commands, and enums; devices instantiate the product.
- The shadow stores reported (device to platform) and desired (application to device) properties; commands can be synchronous or asynchronous.
- Northbound APIs serve applications; southbound APIs serve devices; authentication uses device ID and secret or certificates.
- OTA manages firmware packages and campaigns; the rules engine forwards or transforms data to other cloud services.
- Common device transports include MQTT and CoAP; choose based on power and network reliability.
Worked example
A temperature sensor product has property temperature (decimal, Celsius) and command set_report_interval. Register a device, bind it to the product, then the application subscribes to property changes. Reasoning: the model makes data machine-readable; the shadow holds the last value when the device sleeps; the command changes the reporting interval without reflashing firmware.
Traps
- Mixing product and device: the product is the template, the device is the instance.
- Writing desired properties and expecting immediate device state; the device must report back.
- Using the application API for device registration or the device API for dashboards.