MQTT – the rebirth of a protocol
A little bit of history…
Even though MQTT is today very popular as the IoT / IIoT Protocol, it’s not new at all: MQTT has been first authored in 1999 to monitor oil pipelines within the SCADA network and as a part of the IBM MQ Series Middleware products. The goal was to establish a bandwidth-efficient, lightweight and low-power demanding Machine2Machine (M2M) protocol predominantly for satellite communication of remote devices.
In 2013, IBM submitted MQTT v3.1 to the OASIS specification body with a charter that ensured only minor changes to the specification could be accepted. MQTT-SN (MQTT for Sensor Networks) is a variation of the main protocol aimed at battery-powered embedded devices on non-TCP/IP networks, such as Zigbee. The protocol has been standardized by is OASIS (Organization for the Advancement of Structured Information Standards) in 2014 and has a ISO recommendation (ISO/IEC 20922). A substantial upgrade to the current MQTT v.5 was released in 2019, adding several new features.
How does it work?
MQTT runs mostly over TCP/IP; however, any network protocol that provides ordered, lossless, bi-directional connections can support MQTT.
MQTT is event driven and enables messages to be pushed to clients through the MQTT broker. The communication involves three parties: the message source (i.e. the temperature sensor), the MQTT broker who is orchestrating the communication and finally the MQTT clients, who are subscribed to a particular information.
The MQTT architecture decouples the different participants from each other, enabling a highly scalable solution without dependencies between data producers and data consumers. A client is subscribing to a required information the a MQTT broker (the post office) gets served if a respective information is available.
Due to its history, MQTT is very lightweight and can therefore run on any device or sensor and consumes very little network/communication bandwidth. The message broker philosophy and embedded QoS functionality makes it highly reliable and allows it to scale easily and made MQTT becoming a de-facto IoT standard in Smart Home / Building Automation.
MQTT relevance in Lighting Control
Zencontrol has implemented MQTT support to its application controller (AC) software architecture, allowing the communication between its controllers and a MQTT message broker, allowing a real-time ingestion of DALI ECD and ECG analytics. The MQTT implementation is enabling the zencontrol application