Event-Driven Architecture

What Does Event-Driven Architecture Mean?

Event-driven architecture (EDA) is a software architecture pattern that promotes the production, detection and consumption of, and reaction to, significant changes in a system’s state (known as events). This is applied through the design and implementation of applications and systems that transmit events among loosely coupled software components and services.

Techopedia Explains Event-Driven Architecture

Event-driven architecture compliments service-oriented architecture because these services can be activated by triggers fired on incoming events. Event-driven systems include event emitters and event consumers. Event consumers apply reactions as soon as events are presented. The initial category of event consumers is based on traditional components such as message-oriented middleware, while the second category requires an appropriate transactional executive framework.

Events have two parts:

1. Header: Includes information such as event name, event time stamp and event type
2. Body: Describes what actually happened

Event-triggered architecture is built on four logical layers:

• Event generator
• Event channel
• Event processing engine
• Downstream event-driven activity

The three styles of event processing are:

• Simple event processing
• Event stream processing
• Complex event processing