Description of the illustration adque039.gif

Applications at the top and bottom of the illustration are linked by arrows with an unlabeled queue in the middle. At the top, Application A is linked to the queue with a downward-pointing arrow labeled Enqueue. At the bottom are three more applications, each labeled consumer (subscriber). Application B and Application C each carry the additional label Implicit Recipient and are linked to the queue with solid downward-pointing arrows labeled Dequeue. Application D carries the additional label Explicit Recipient and is linked to the queue with a dashed downward-pointing arrow.