When the remote unit is operating within a cellular network, where data traffic is billed per volume, the connection between the cloud server and the physical unit can be managed in order to keep data traffic within reasonable limits.
WiFi is the first choice (when available). Fallback to cellular network, when SIM card is installed and PLMN enabled.
The unit will establish a connection when there are data to upload or messages to send.
Communication protocol is very efficient, thus data volume is reduced to minimum.
These settings affect both the cellular and Wi-Fi connections.
SMM > mintime
To prevent too frequent uploads, it's possible to set the minimum time interval between consecutive data transfer in the range 1 to 1440 minutes ( 24 hours ). If one ore more events occur within this time, the unit will postpone the upload sending everything in a single session.
SMM > keepalive
A periodic small transmission could be required to keep a permanent connection.
The unit can send a couple of bytes periodically, so as not to allow too much time between consecutive transmissions.
If the connection is interrupted due to long inactivity period, the connection will be restored when the device will need to send data, but meanwhile it will not be possible to receive commands in real time from the server .
Default setting of 10 minutes is suitable for most of situation and involves a data traffic of 24k/day approx.
When the network policy is more aggressive (closing a connection in a shorter time, specially in PLMN) this interval could be reduced down to 1 minute, increasing the amount of data used to keep the connection alive.
Of course any additional data exchanged with remote unit will produce additional data traffic.
Set 0 (zero) to disable this feature.
SMM > server
Data will be fetched from and posted to a Socket Messages Management broker located at this public address, set as a domain name or IPv4 address.
Contrive provides a SMM cloud server for free, the one that allows the access to these APIs.
This service will be lost changing the default address:
http://www.mobikey.eu or https://www.mobikey.eu