Broker Pattern

The broker pattern is an architectural pattern that can be used to structure distributed software systems with decoupled components that interact by remote procedure calls. A broker component is responsible for coordinating communication, such as forwarding requests, as well as for transmitting results and exceptions.

Broker Pattern Roles

• Client: access server’s functionality by sending requests to the broker.
• Server: it make their services available on the broker.
• Broker: find the appropriate server, forward the request and transmit result to client.

Broker pattern has the following characteristics

• A broker component coordinates requests and responses between clients and servers.
• The broker has the details of the servers and the individual services they provide.
• Clients send requests, and the broker finds the right server to route the request to.
• It also sends the responses back to the clients.

Message Queue vs. Message Broker

A message queue is a form of describing a data structure to hold messages for eventual consumption. Where a message broker is a separate component that manages queues.

In simple words a message queue is a queue like data structure first-in-first-out (FIFO). A message broker is more like service bus; an object that is used to route traffic while allowing to decouple the system into smaller parts.

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