At-least-once Delivery

In case of failures that lead to message loss or take too long to recover from, messages are retransmitted to assure they are delivered at least once.

At-least-once Delivery How can communication partners or a Message-oriented Middleware ensure that messages are received successfully?


Sometimes, message duplicity can be coped with by the application using a Message-oriented Middleware. Therefore, for scenarios where message duplicates are uncritical, it shall still be ensured that messages are received.


For each message retrieved by a receiver an acknowledgement is sent back to the message sender. In case this acknowledgement is not received after a certain time frame, the message is resend.

At-least-once Delivery

Idempotent Processor, Timeout-based Delivery