Web services are deployed to invoke remote calls over HTTP/HTTPS. To make calls such as these, requires that information about the calls be shared with the end client. In the past, during the days of CORBA, developers used to share IDL (Interface Definition Language) files providing the required information over the network. Now, in the days of web services this has changed to WSDL (Web Services Definition Language). WSDL is a major source for information and can help in the enumeration process. We shall go over the enumeration process in subsequent sections.
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