How do you describe interaction through a message broker?

Message broker interaction is an architectural approach where system components exchange messages through an intermediary — a message broker.

The message broker receives messages from senders (publishers) and delivers them to recipients (subscribers) according to certain rules.

Main features:

• Asynchronous: the sender does not wait for an immediate response, which increases system resilience and scalability.
• Decoupling of components: the sender and receiver do not know about each other directly, interacting through the broker.
• Reliable delivery: brokers often support acknowledgments, retries, and message persistence.
• Routing and filtering: the broker can direct messages by topics, queues, or other criteria.

Example: in a microservices system, an order service sends a message about a new order to the broker's queue (e.g., RabbitMQ). The payment processing service subscribes to this queue and receives the message to start processing the payment.

Thus, the message broker provides flexible, scalable, and reliable interaction between distributed system components.