Because Web Service request (input) and response (output) messages are asynchronous, if an Apama application needs to correlate response messages with a specific request message, you need to specify a field in the Apama event that will contain the correlation ID information.

To use correlation IDs to associate response messages from Web Services with request messages from Apama applications, specify the name of the event field that will contain the correlation ID by selecting the field in the Input Correlation Field, Output Correlation Field, and Fault Correlation Field drop-down lists. Do this for each event (input, output, and fault) that you associate with the operation. These drop-down lists are located on the Input Output, and Fault tabs, respectively.

In the following image of an Input Mapping Events tab, you can see the Input Correlation Field at the top of the tab, and the corrField field in the input event tree. There is no need to map the correlation ID field. The adapter automatically takes care of this.