Communication patterns
The upper connectivity layer to a cloud service is usually based on publisher/subscriber patterns but in some cases it can also be based on polling patterns. TC3 IoT Data Agent implements the connectivity with the cloud service and provides this access via an abstracted way of communication to TC3 IoT Functions. The PLC library of TC3 IoT Functions then uses this interface then via a polling read/write pattern.
Example
TC3 IoT Functions should be used to read messages from Azure IoT Hub. Connectivity with this cloud service is based on the publisher/subscriber pattern. This means that TC3 IoT Data Agent is configured with access credentials to the IoT Hub service and will therefore provides connectivity to it. TC3 IoT Functions then polls the TC3 IoT Data Agent for any incoming messages.
Message buffer
TC3 IoT Data Agent includes a message buffer for incoming messages that should be used by TC3 IoT Functions. This message buffer can be set directly on the corresponding TC3 IoT Functions channel.
