Message Queuing (MQ) is a form of communication in which messages are exchanged via intermediate queues (store and forward) instead of being directly exchanged. Because there is no synchronization between the sending and receipt of messages, message to message queues are also called asynchronous messages. Communication takes place by means of asynchronous jobs. An asynchronous job consists of the asynchronous message, the recipient of the message and possibly also the desired time of execution.
openUTM provides you with two types of message queues:
UTM-controlled queues:
In the case of UTM-controlled queues, the interposed queuing mechanism is made available in its entirety by openUTM. In other words, in addition to pure queuing functionality, openUTM also takes on the subsequent processing of the message (e.g. output to a communication partner or startup of a service).Service-controlled queues:
In the case of service-controlled queues, a service is responsible for the further processing of the message. In other words, openUTM provides only the queuing functionality. The communication partner for whom the message is intended must read the message from the queue independently (using the KDCS call DGET). If there is no message in the queue, a service can also wait for the arrival of a message.
Unix, Linux and Windows systems
In UTM cluster applications message queuing is only supported locally in the node. This means that asynchronous messages can only run and be read, displayed or administered in the node application in which they were created.
The one exception is that you can transfer asynchronous jobs from a terminated node application into a running node application using the online import facility.