what is asynchronous communication
Synchronous and Asynchronous Communication. All communication to a COM or Script component implementation is synchronous. If you want to create a communication flow to a port that uses a COM component or Script component implementation, you must use the Method Communication Wizard. All communication to an unbound port, or to a Message Queuing or BizTalk Messaging implementation is asynchronous. If you want to create a communication flow to a port that uses a Message Queuing or BizTalk Messaging implementation, or if you want to create a communication flow to an unbound port, you must use the XML Communication Wizard.