Many message queues are designed to provide a lightweight publish/subscribe messaging protocol for your application. Why and when do you use message queues in your Internet of Things project?
Consider a temperature sensor in a greenhouse, which measures the temperature. Your application can send the temperature to the message queue at 15-minute intervals (96 times per day per month). Instead of processing the data in the greenhouse and always connecting.
Message Queuing for the Internet of Things is designed to provide lightweight publish/subscribe message transport. Instead of keeping an application that processes greenhouse data, you simply send the data and process it in another service. This requires less network bandwidth, which can limit your sensors, or your sensors can communicate over a satellite link.
Message queues enable your application to have low power consumption, send minimal packets, and efficiently distribute information to one or more receivers.
Message queues in IoT projects
Message Queuing is a means of service – to – service communication. It allows applications to communicate by sending messages to each other. The basic architecture of message queues is simple, and there are client applications that can create messages and deliver them to message queues. Other applications/services retrieve messages from the queue and process the requests and information contained in the messages
Messages can contain any type of information. For example, it could get information about a process/task that should start in another application (possibly somewhere else), or it might just be data that needs to be processed.
Internet of Things and Asynchronous Messaging
Internet applications that are reactive and asynchronous are a “must.” Most IoT applications should be able to handle many connections from the device and all messages passing from it
Asynchronous messaging is widely used in machine-to-machine communication. This means that the sender does not expect an immediate response, and the sender does not “block” anything while waiting for the response.
Asynchronous communication allows for flexibility in that the application can send a message and then move on to other things – in synchronous communication, it must wait for a real-time response. Instead of calling the Web service and waiting for it to complete, you can write the message to the queue and let the same salesman logic happen.
Queues can be great in situations where your application needs to do something but doesn’t need to do it right away, or doesn’t even care about the results.
Message queues can be used to decouple and help keep the structure flexible. It makes it very easy to connect two different applications written in different languages.
Message queues allow each component to perform its tasks independently – it allows components to remain fully autonomous and unaware of each other that changes to one service should not require changes to other services. It is the process of separating services so that they function more independently.
Redundancy and elasticity
Apps sometimes crash – it happens. This may be due to timeouts or because only errors in your code affect the entire application. Message queue enforcement enables the receiving application to confirm that it has completed the task and can safely remove the task from the queue. If any content in the receiving application fails, the message remains in the queue.
Message Queuing provides a temporary message store when the target program is busy or disconnected.
By breaking up your application and separating different components by queue, you inherently create more flexibility. Your application can still run even if part of the back-end processing is delayed.
The rush hour
Many applications saw a surge in traffic. Doorbell app that lets you answer your door from anywhere, Halloween may have rush hour, and shopping app that may have rush hour on Black Friday. By queuing your data, you ensure that your data is eventually retained and processed; Even if that means it takes longer than usual due to high traffic spikes.
Use RabbitMQ to queue IOT messages
There are IoT communication protocols and standards that aim to simplify IoT design. If you are considering a queue-based solution, CloudMQP offers two of the most popular open messaging protocols; AMQP and MQTT are via RabbitMQ.
AMQP is a secure and reliable protocol with low overhead, which is very suitable for IoT applications. AMQP is a more advanced protocol than MQTT, which is more reliable and better supports security. AMQP also has flexible routing, persistent and persistent queues, clustering, federation, and high availability queues. The downside is that it is a more verbose protocol – depending on how you implement your solution.
MQTT is another protocol designed for the Internet of Things. The IoT benefits advertised by MQTT apply only to devices with extreme power consumption. MQTT is very energy efficient and it focuses on minimizing line footprint. Because of its simplicity, implementing MQTT on the client side requires less work than AMQP. However, MQTT lacks server-to-client authorization and error notification, which is a big limitation.
RabbitMQ is a message queuing software, called a message broker or queue manager. Simply put, it is software that can define queues to which applications can connect and transfer messages.