If Your Gateway Heartbeat is Less Frequent than Your Sensor

A consideration that should be made when setting up heartbeats for your devices is how those heartbeat settings can have an effect on how information will be displayed on the iMonnit portal.

Monnit sensors and gateways both utilize a heartbeat to determine the interval that the devices check in. The sensor will communicate with the gateway on the sensor’s heartbeat, and the gateway will communicate with iMonnit on the gateway’s heartbeat.

If the sensor has a heartbeat that is more frequent than the gateway’s heartbeat, then this creates a situation where the gateway will receive the information from the sensor but will not send that information until the gateway’s heartbeat. This will cause a sensor’s messages to be delayed. When the gateway sends its message, it will then send any messages it had in its queue.

A second consideration to make is in the case of an aware state. A gateway can have a setting enabled called “On Aware Messages”. If set to Trigger Heartbeat then the gateway will immediately send the message if the sensor is sending an aware message.

Example

A sensor has a heartbeat of 10 minutes, and the gateway 15 minutes.

1. Gateway checks in and sends messages to iMonnit at 10:00:00.
2. Sensor checks in and messages gateway at 10:01:00.
3. Gateway receives communication and holds it in memory.
4. Sensor checks in and messages gateway at 10:11:00.
5. Gateway receives communication and holds it in memory.
6. Gateway checks in and sends messages to iMonnit at 10:15:00.
7. The two previous sensor messages are now uploaded with timestamps of 10:01:00 and 10:11:00.