Event Broker Definition:
An event broker is message-oriented middleware that enables the transmission of events between different components of a system, acting as a mediator between publishers and subscribers. It is the cornerstone of event-driven architecture, and all event-driven applications use some form of event broker to send and receive information.
An event broker can be hardware, software, or software-as-a-service (SaaS).
A network of event brokers is called an event mesh.
Event Broker vs. Message Broker
Event brokers and message brokers both establish loosely coupled relationships between applications using message exchange patterns like publish/subscribe and request/reply, or combine multiple patterns, depending on the specific requirements of the interaction.
They both support various qualities of services such as non-persistent and persistent delivery through the use of queues, but generally speaking message brokers are better at point-to-point and queue-oriented data exchange, while event brokers are better at real-time publish/subscribe interactions.
What features should an event broker support?
Some of the advanced features that an event broker should provide include:
- Stream processing
- Various delivery modes, including “exactly once,” “at most once,” or “at least once”
- Persistent event ledger for analysis and event sourcing
- Security at various levels of authentication, authorization and topic/channel access control
- Programmable extensibility for custom filtering and analysis
- High availability and disaster recovery
What are the best event brokers?
Gartner lists these products as the top 5 best event brokers in their “Event Broker” category for Peer Insights reviews and ratings (2023):
- PubSub+ Platform – by Solace
- Microsoft Azure Event Grid – by Microsoft
- IBM MQ – by IBM
- Confluent Cloud – by Confluent
- TIBCO Messaging – by TIBCO Software
Here is a summary of Gartner’s advice on how to choose an event broker.
Learn About PubSub+ Event Broker
PubSub+ Event Broker is available as run-anywhere software, purpose-built hardware, and a managed service that can stream events across the distributed enterprise. It supports a wide range of message exchange patterns beyond publish/subscribe, including request/reply, streaming and replay, as well as different qualities of service.
PubSub+ Platform encompasses the event streaming capabilities of the event broker as well as the ability to manage and monitor the event-driven ecosystem.
Read more here or watch the quick explainer video below.