Asynchronous transmission introduces the concept of assured message delivery. When delivering messages asynchronously, MQe delivers each message once, and once-only, to its destination queue. However, this assurance is only valid if the definition of the remote queue and remote queue manager match the current characteristics of the remote queue and remote queue manager. If a remote queue definition and the remote queue do not match, then it is possible that a message may become undeliverable. In this case the message is not lost, but remains stored on the local queue manager.