What is a message queue? A message queue refers to a list or series of actionable work objects waiting to be dealt with by an agreed-upon IT process.
Message queues allow for communication and coordination between various distributed applications, allowing different parts of a system to communicate with each other and to and process operations asynchronously.
A message queue serves as a lightweight buffer that temporarily stores messages, and provides endpoints that allow software components to connect to a queue in order to send or receive messages. These messages are usually small, things like requests, replies, error messages, or alerts about a finished task. The "message" is transported between a producer (sending) and a consumer (receiver) application.
The basic architecture begins with producers, which create these messages and then deliver them to the resulting message queue. The messages are then stored until the message is retrieved by the consumer. Easy functionality is key for IT experts as there are usually priorities, so not having to immediately act on a message creates a bit of a buffer when managing many buckets at a time.
Message queues are part of an everyday enterprise and do not always require an immediate response. Some message queues are known as an asynchronous communications protocol (ACP), which, by definition, is waiting for response based on the receiver. The best example of asynchronous messaging is email. When the email is sent, the sender is able to process all other work without having to receive an immediate response from the receiver, decoupling the producer of the data to the consumer. No interaction is required with the message queue by both participants at the same time. A message queue makes it possible to keep processes in an application separate and independent.
The best message queue systems are extremely user-friendly, easy to scale ,and easy to maintain. An IT department is often mobile and able to access the message on premises or with mobile tools. This lends itself to flexibility and maximizes productivity.
The features of message queuing software include:
Asynchronous Messaging - Programs are time-independent, meaning they can make a request and then continue with other work while waiting for a response. Messages will remain in the queue until they are processed and then removed. The target application can retrieve a message whenever it starts up - it does not have to be running when a message is sent.
Programs are not directly connected. Instead, one program puts a message on a queue and the other retrieves the message from the queue.
Small, self-contained programs can divide up the job instead of being performed entirely and sequentially by a single large program. A message gets sent to each program, requesting it to perform its function and then the results are sent back as messages.
Unlimited queues that can handle as many messages as necessary.
Real-time message processing so that requests get handled as soon as possible .
Push and pull queues - The pull feature looks for new messages while the push feature notifies the user when a message is available. Push is also called “publish/subscribe” or “pub/sub” messaging.
First in, first out (FIFO) - Messages are processed in the order in which they come in.
Message priority - Programs can assign a priority to each message, determining its position in the queue.
Message-driven processing - Apps can be triggered when a message arrives and stopped when a message has been processed.
Event-driven processing - You can control the programs according to the state of the queue. E.g. you can set the program to start as soon as one message arrives on the queue, or once 10 messages have arrived on the queue, or once a certain number of messages above a particular priority have arrived.
One-time delivery so there are no duplicate requests which might lead to confusion. It also means the network won’t be slowed down by unnecessary requests.
Automatic failover - There are multiple cloud systems so if one network fails, another can pick up the slack, avoiding delays.
Message queue as a service (on a cloud server versus on your on-site network).
High network availability so that messages can be processed as quickly as possible and to reduce the likelihood of outages, which improves efficiency and keeps customers happy.
Scalability - Cloud-hosted message queues allow you to access more processing power whenever you need it.
Security, which includes passwords, authentication tokens, and simple authentication and security layers (SASLs).
Serverless - With no server to manage, your IT team can focus on other tasks.
Recovery support in case of lost messages.
The benefits of message queue software include:
1. Improved performance. Message queues enable asynchronous communication between and within apps. This means the endpoints that produce and consume messages interact with the queue and not with each other. Producers can add requests to the queue without having to wait for them to be processed, and consumers only process messages when they are available. In this way, neither component in the system has to wait for the other, which optimizes data flow.
2. More reliable. Queuing your data makes it persistent and reduces the risk of errors happening when parts of your system go offline. Separating different components into message queues creates fault tolerance. In addition, any time one part of the system is unreachable, the other part can continue interacting with the queue. The queue can also be mirrored, allowing for even more availability.
3. Granular scalability. Producers and consumers as well as the actual queue can be scaled on demand.
4. Simplified Decoupling. Using a message queue removes dependencies between components and simplifies the coding of decoupled applications. Software components can be designed to perform discrete business functions rather than being weighed down with communications code.
