This example illustrates a formal verification of service interactions.  The service communication models either a synchronous "invoke only", synchronous "invoke-reply" or an asychronous "invoke-receive" interaction.

In Test 1 the interaction verification caused a violation for the buyer-marketplace requireProduct operation.  Test 2 solves the violation by adding a reply to the Marketplace process.

To perform the verification:

1  In LTSA WS-Engineer switch to the Interactions tab 
2. Select both the buyer.bpel and buyer.wsdl files and drag-and-drop on to the "Processes and Interfaces" listbox on the tab page.
2. Select both the marketplace.bpel and marketplace.wsdl files and drag-and-drop on to the "Processes and Interfaces" listbox on the tab page.
4. Click Verify and note no violation is detected.
