In the last chapter, we learned about conversations. However, we now need to associate a message with the instance to which it belongs. This message association with the conversation is performed using the correlation mechanism. The correlation mechanism enables the identification of a correct instance in another process through an instance, and it enables us to send a message to that specific instance.

We can use correlation to communicate between the BackOffice process, web process, and Loan Origination process. When the Loan Origination process completes a loan process for an applicant, it sends a message to the BackOffice process or web process, whichever has initiated the Loan Origination process, using the Applicant ID to locate the instance in both processes. The correlation is done using the Applicant ID.