To receive documents, a client must register a subscription on the Broker. A subscription identifies the type of document the client wants to receive. If the client wants to receive only certain instances of a particular type, it can attach a filter to the subscription. When a subscription includes a filter, the subscriber receives only the documents that satisfy the filter criteria.

Subscriptions are registered by the client programs that interact with the Broker. When a developer creates a trigger on an Integration Server, for example, the Integration Server registers a subscription on the Broker for each document type associated with the trigger.

When Broker receives a document for which there are no subscribers, it puts the document in the dead letter queue (if one is configured). If a dead letter queue has not been configured (which is the installed behavior), the document is discarded.

You can use the Broker user interface to view the subscriptions for a client and to delete a subscription. You can also use the Broker user interface to discover which clients subscribe to a particular document type.

For more information, see Managing Subscriptions and Viewing Which Clients Subscribed to a Document Type.