MQTT - System Protobuf TCP

5 min

overview mqtt system protobuf tcp integration enables an edge system to connect with a system protobuf broker supported versions mqtt protocol version 3 1 0 mqtt protocol version 3 1 1 supported communication outbound (publish data from edge to mqtt broker) yes inbound (subscribe data from mqtt broker to edge) yes configurations variable detail required name enter a name for the connector yes hostname ip address or server fqdn of mqtt broker (must be reachable from the edge system) yes port mqtt broker port no clientid unique client identity yes username user name yes password user password yes qos the quality of service (qos) level is an agreement between the sender of a message and the receiver of a message that defines the guarantee of delivery for a specific message you can publish several messages simultaneously when you publish, a larger value allows more throughput but may lead to packages losing messages despite assigning qos=1 note the qos option depends upon the server configuration no parallel publish count for example, mosquitto has the following options max queued messages (100 by default) max queued bytes (0 by default) according to the mosquitto documentation, once this limit has been reached, subsequent messages are silently dropped you can modify the server configuration or set this value in accordance with the server option yes topic default topic for publishing or subscribing yes throttling limit set a limit on the number of outbound messages per second if sending data to a server that has restrictions on the rate of incoming messages, this ensures that no messages are lost no persistent storage if enabled, messages in the outbound queue are stored on disk if there are interruptions in connection or power loss, messages will be retained and eventually sent when the connection is restored no queue mode select the sequence of data transfer fifo or lifo selecting fifo (first in first out) will send the earliest message first selecting lifo (last in first out) will send the latest message first no compatibility validation this information is just for reference more products and versions may be supported provided they are compatible with the supported version as mentioned above product version date mosquitto message broker 1 x nov 14, 2019 hivemq 2 x nov 14, 2019