Telemetry
What is telemetry
Telemetry addresses collecting and transmitting data from your device to the Kaa Platform. Telemetry includes but not limited to data collection, remote monitoring, real-time insights, etc. Kaa tightly interconnects telemetry term with other terms like data sample, time series, and data point.
What you can do with telemetry using Kaa
Kaa provides you with the next features regarding telemetry:
- Upload telemetry from device using Device MQTT or HTTP APIs
- Monitor traffic coming from and to device
- Visualize telemetry
- Transform telemetry into time series
- Process telemetry with Rule Engine
- Configure alerts on telemetry values
- Retrieve telemetry using REST API
Upload telemetry from device using MQTT or HTTP
You can upload telemetry data from your device using the next Device APIs:
Refer to Connecting your first device from Getting Started for deeper knowledge.
Monitor traffic coming from and to device
Once your device starts sending telemetry into Kaa, the first thing you can do to check if it was successfully delivered is to check device’s logs via Kaa UI.
Go to Device management -> Devices -> your device -> “Data logs” tab
Visualize telemetry
Kaa UI provides rich set of widgets that you can use to visualise telemetry data. Let’s go through some of them.
Charts
Gauges
Maps
Labels
Transform telemetry into time series
Kaa can transform telemetry into time series. Time series is a named sequence of data points. Each data point contains a timestamp and one or more named values. A set of value names and their types (numeric, string, boolean) defines a time series.
You may want different time series defined for various things.
For example, a fuel level time series may only have one numeric value: level.
On the other hand, a geolocation time series may have several numeric values: latitude, longitude, and in some applications altitude.
You can configure Kaa to transform data samples (telemetry) received from endpoints into time series for displaying them on charts, gauges, maps, etc. as mentioned above.
Also, Kaa has an auto-extraction feature that stores each numeric top-level data sample field into a separate time-series.
All auto-extracted time series have a name that follows the pattern auto~<field name> and one numeric value with the name value.
So, if your endpoint sends data a sample with two fields, e.g.:
{
"temperature": 23,
"humidity": 48
}
and the auto-extraction feature is enabled, Kaa creates two time-series: auto~temperature and auto~humidity.
You can enable auto-extraction feature in Device management -> Applications -> your application -> “epts” (Kaa component that is responsible for time series processing).
Process telemetry with Rule Engine
Once telemetry is in Kaa, you can apply various rules with the help of Rule Engine. Rule Engine allows you to write rules of any complexity using the most popular programming language in the world - JavaScript.
Processing telemetry data with Rule Engine you can perform the next things in real time:
- Generate alerts base on telemetry values
- Execute webhooks
- Invoke command on device
- Update device metadata
- Modify or enrich incoming data before storing it
- Find delta between previous and current telemetry value
- Run complex calculations based on real-time plus historical data
Visit Rules section in Kaa UI and explore Rule Engine capabilities. Rule Engine documentation section will give you more details.
Configure alerts on telemetry values
Kaa can monitor incoming telemetry in real time and create alerts once preconfigured condition is met. Alerts are built on top of Rule Engine.
Visit Alerts -> Alerts settings section in Kaa UI and explore alert capabilities.
Retrieve telemetry using REST API
Refer to REST API documentation on how you can retrieve telemetry.