Events are notification messages published to a specific topic. Web services can subscribe to a topic in order to receive events that are published to it, allowing web services to publish and subscribe to each others' notifications.
The Topic Browser in the Management Console allows you to create, manage, and subscribe to topics, and the Event Mediator makes it easy for your proxy service or sequence to publish a received request or response to a topic as an event. Eventing in the ESB of WSO2 Enterprise Integrator (WSO2 EI) is based on the WS-Eventing Specification. The following pages describe how to work with topics in detail: