Addressing information

When an application puts messages that are destined for a remote queue manager, the local queue manager adds a transmission header to them before placing them on the transmission queue. This header contains the name of the destination queue and queue manager, that is, the addressing information.

In a single queue manager environment, the address of a destination queue is established when an application opens a queue for putting messages to. Because the destination queue is on the same queue manager, there is no need for any addressing information.

In a distributed queuing environment, the queue manager needs to know not only the destination queue name, but also the location of that queue (that is, the queue manager name), and the route to that remote location (that is, the transmission queue). This addressing information is contained in the transmission header. The receiving channel removes the transmission header and uses the information in it to locate the destination queue.

We can avoid the need for our applications to specify the name of the destination queue manager if we use a remote queue definition. This definition specifies the name of the remote queue, the name of the remote queue manager to which messages are destined, and the name of the transmission queue used to transport the messages.