The Server
Server applications must be allowed to subscribe to all of the event types that are to be processed. In response to a request event, servers must also be prepared to deliver a reply event of the expected type. Generally, your server application should follow these steps:
1. Check for permission to subscribe to the request event types.
2. Check for the appropriate reply event publishing permissions.
3. Retrieve an event and process it.
4. Deliver the appropriate reply event(s).