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SECTION 1
Introduction
An event-driven architecture (EDA) is an architecture pattern designed to connect service
components and enable complex systems to communicate. Event-driven architectures are
comprised of three key components:
1. Event producers (e.g., software as a service (SaaS) app, mobile app, ecommerce site,
point-of-sale)
2. Event brokers (e.g., event router, event store)
3. Event consumers (e.g., database, microservice, SaaS application)
Events indicate a change in state (order placed, user created) and are passed between components
as messages with specific semantics. A producer publishes an event to the broker, which abstracts
producers and consumers from one another by allowing them to communicate asynchronously.
EDAs use events to coordinate communication between loosely coupled services.
Event sources
AWS services
Default event bus
Custom event bus
SaaS event bus
Custom events
SaaS apps
Event targets
AWS Lambda
Amazon Kinesis
AWS Step Functions
Amazon API Gateway
Buses in other accounts