Business event dispatch queue types

z/TPF business event dispatch queues can be classified as unordered, ordered, or remote. Each dispatch queue type has different properties.

Unordered dispatch queues

When you use an unordered dispatch queue to process business events, multiple dispatch ECBs can process those events. As a result, events might be processed in a different order than the order that they were added to the dispatch queue. The z/TPF system automatically creates and manages dispatch ECBs as needed.

You can use the ZBEVF SET command with the MAXECBS and DISPQUEUE parameters specified to set the maximum number of ECBs that can be used to process events from each unordered dispatch queue. If you do not specify the MAXECBS parameter value, business event processing uses the default value of 1.

You can use the following two types of unordered dispatch queues:
  • The system default dispatch queue named IBEV.UNORDERED.DISPATCH.QUEUE. The system default dispatch queue is created as part of the instructions in Configuring and enabling business event processing. To use the system default dispatch queue, take one of the following actions:
    • Do not specify the optional element <esDispatchQueueName> in the business event specification.
    • Specify the optional element <esDispatchQueueName> with the name IBEV.UNORDERED.DISPATCH.QUEUE in the business event specification.
  • An unordered user-defined dispatch queue, which can be any dispatch queue, aside from the system default dispatch queue, with a name that starts with IBEV.UNORDERED.. To use an unordered user-defined dispatch queue, specify the optional element <esDispatchQueueName> in the business event specification with the name of the unordered user-defined dispatch queue.

You can use an unordered dispatch queue to process any type of business events, including signal events, data events for z/TPFDF files, and data events for z/TPF files.

Ordered dispatch queues

When you use an ordered dispatch queue to process business events, events are read, formatted, and transmitted in the same order that they are placed on the queue. To maintain the order of events, business events processing uses only one dispatch ECB to process events on the queue.

To use ordered dispatch processing, specify the optional element <esDispatchQueueName> in your business event specification with the name of an ordered user-defined dispatch queue. An ordered dispatch queue is any queue with a name that does not start with IBEV.UNORDERED..

You can use an ordered dispatch queue to process signal events and data events for z/TPFDF files. You cannot use an ordered dispatch queue to process data events for z/TPF files.

Remote dispatch queues

When you use a remote dispatch queue, business event processing uses IBM MQ to send the created events to another z/TPF system for dispatch processing.

You can use a remote dispatch queue to process the following events:
  • Signal events
  • Data events for z/TPFDF files, if you specified a value of Updates for the <collectionType> element in the business event specification.
You cannot use a remote dispatch queue to process the following events:
  • Data events for z/TPF files
  • Data events for z/TPFDF files, if you specified a value of Subfile for the <collectionType> element in the business event specification.

For more information about remote dispatch processing, see Plan for business event dispatch queue and dispatch processing and How z/TPF business event remote dispatch processing works.