The following illustration shows the payment and the resulting acknowledgement flow through the supplier system.
Supplier system receives a payment and sends back an acknowledgement
The supplier's XML Web service accepts the incoming payment for the invoice that it issued. The XML Web service submits the payment to a BizTalk Messaging Services channel configured for payment processing. Then the pipeline component on that channel correlates the incoming document with an XLANG schedule instance identifier. This correlation information is obtained by reading the key-pair values from the supplier custom correlation database. The payment is sent to the correlated XLANG schedule instance, and resumes processing on the ReceivePayment port. After the document is back in the schedule, it is sent to a component that transforms the payment into a payment acknowledgement. The payment acknowledgement is sent to the SupplierSendPaymentAck channel for further processing. When the processing completes, the payment acknowledgement is sent back to the hub by means of an AIC that functions as a client to the hub's XML Web service. At this point, the supplier XLANG schedule for this transaction completes.
The XLANG schedule instance on the hub system completes after it receives the payment acknowledgement, correlates it to the correct purchase order, and writes the acknowledgement document to the folder \Microsoft .NET Server Solutions for the Enterprise\E-Procurement\Application\eprocurement\PaymentAckReceived.