Transmission queues

 

When an application sends a message to a remote queue, the local queue manager stores the message in a special local queue, called a transmission queue.

A message channel agent (channel program), or intra-group queuing agent when using intra-group queuing on WebSphere MQ for z/OS, is associated with the transmission queue and the remote queue manager, and this delivers the message. When the message has been delivered, it is deleted from the transmission queue.

The message might have to pass through many queue managers (or nodes) on its journey to its final destination. There must be a transmission queue defined at each queue manager along the route, each holding messages waiting to be transmitted to the next node. (A shared transmission queue is used when using intra-group queuing on WebSphere MQ for z/OS.) There can be several transmission queues defined at a particular queue manager. A given transmission queue holds messages whose next destination is the same queue manager, although the messages might have different eventual destinations. There might also be several transmission queues for the same remote queue manager, with each one being used for a different type of service, for example.

Transmission queues can be used to trigger a message channel agent to send messages onward. For information about this, see Starting WebSphere MQ applications using triggers. These attributes are defined in the transmission queue definition (for triggered channels) or the process definition object (see Process definitions).

 

Parent topic:

Queues

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