The external system interacts with Business Process Server using event gateways. An event gateway ensures that, all the events received by it are persisted and processed. An event gateway supports JMS to accept external events.
The external system can send events as JMS messages to a pre-decided and pre-configured queue to create a monitoring process instance or to process the various steps involved as part of the monitoring process. These messages are processed by a MessageDrivenBean in Business Process Server.
Monitoring Process Queue is a persistent queue. Messages sent to this queue are persisted irrespective of the message delivery mode set by message sender (external system).
Note: To ensure that the messages are not lost even in the case of application server like JBoss, which does not support persistent JMS destination, Progress Software Corporation recommends that the external system must send all monitoring process JMS messages using persistent delivery mode.
