Reliable Messaging

This topic describes reliable messaging.

Reliable messaging uses a queue to ensure that Web service message calls are not lost due to unavailability of the back-end. For example, if the back-end is down the Web service calls will stay in the queue till the back-end is up. As a result, the Web service call can take a long time if the Web service call is not handled directly. Therefore, Web services called via reliable messaging are asynchronous by nature. So, in a business process the output message can neither be used nor can exceptions be handled for Web services called via reliable messaging.

Hence, reliable messaging is recommended for Web services for which it is essential, that they, are always executed and executed only once; and for those Web services for which the functionality cannot go wrong. For example update Web services calls which can never have primary key violations and do not contain invalid data.