In two-way Web services interaction, at each end point of Web service, both the client and server are required. Therefore,
an interaction requires two appropriate WSDLs, one at each end point [1]. These two WSDL interfaces must be correlated
in a certain way to make two-way interaction possible. From the perspective of an end point,
two-way full duplex Web services interaction involves both client-initiated service requests and proactive server pushes for event notification