Azure IoT Hub is nothing but a cloud service that works or serves as a central messaging hub for communication between IoT applications and the devices connected to them.
Azure IoT Hub helps you to safely and securely link an appreciable amount of devices and their backend solutions.
MQTT is short for – “Message Queuing Telemetry Transport”, which is the fundamental thing that one needs to be aware of about MQTT. It’s a communications standard created exclusively for Internet of Things (IoT) applications.
Andy Stanford-Clark and Arlen Nipper worked at IBM’s Cambridge software lab. They were the hands behind the creation of MQTT.
- It uses a publish-and-subscribe architecture;
- The protocol has become particularly popular with the Internet of Things as it makes it simple and convenient to link or connect several devices or sensors.
- Under the OASIS standard, the MQTT protocol is based on TCP/IP.
AZURE IoT HUB
Azure IoT Hub provides a one-stop solution for the back-end to connect to any device possible, it is a cloud-hosted solution.
An IoT Hub can connect to any device, device-to-cloud telemetry, uploading files from devices. It can request-reply techniques to manage your devices from the cloud are all supported communications patterns.
Azure IoT also supports and assists monitoring, and it allows you to note and keep track of device creation, device connections, as well as any sort of device failures.
Azure IoT Hub offers a hand to organizations across various industries, thereby, helping them in improving their business and achieving their IoT goals.
WORKING OF MQTT
The MQTT protocol uses a mechanism of publish-and-subscribe, as mentioned before. Messages can easily be transmitted between client and server using this mechanism. Hence, making it possible for all the IoT devices to communicate with one another without the concern of their geographical location.
During unstable or unresponsive network connections, the MQTT protocol makes sure that the messages are delivered regardless and even employs an acknowledgement system that informs both parties if data has been received appropriately.
Broker for MQTT
To simply say, the broker for MQTT is the system’s nerve centre. It is in charge of receiving all messages, filtering them, and forwarding them to subscribers, who in this case are MQTT clients. Many of the MQTT customers can be dealt with in this fashion.
Client for MQTT
A client is a device that can send and receive messages by interacting with the broker. A client can be a small IoT sensor that sends data at regular intervals or even a smart computer program that displays IoT data in a graphical format.
A client has the prerogative of subscribing to a topic in the broker to get the messages that are specifically associated with that particular subject.
In the same way, a client can also publish messages under a specific topic, which the broker will transmit to the subscribers of that subject.
The Relationship Between Azure IoT Hub And MQTT
- MQTT has been one of the most popular protocols for IoT applications in contemporary years. It is one of the most convenient protocols currently in use in the IoT.
- Client libraries for all major programming languages are available, making it simple to create IoT applications utilizing MQTT.
- This protocol allows scalable projects to be implemented and further potentially links several IoT devices in a single system. MQTT’s bidirectional connectivity allows you to send messages to a large number of devices at the same time rather than sending them one at a time.
- Many ready-to-use services are available through the Azure Portal and may be integrated right away. The final components are then connected to construct cloud apps. One of these components is the IoT hub, and it acts as the fundamental bi-directional connectivity for external data sources and IoT devices.
- The OPC Router is responsible for connecting the IoT Hub and, as a result, the Azure Cloud, thereby, allowing data to be written to the Cloud and the data to be obtained from the Cloud at the field level.
- The OPC Router’s different plug-ins are then used to implement data transmission at the field level or data procurement for the cloud.
The IoT Hub acts as a data entry solution for the Microsoft Azure Portal.
MQTT can be used as a medium of communication with the IoT Hub. MQTT is versatile and hence this versatility allows it to accommodate a wide horizon of use cases and IoT project topologies. The broker manages all connections, therefore, neither the publishers nor the subscribers of the system or subject are made aware of each other’s existence and presence.