Way, way back in the early days of .NET and the abortive Windows Longhorn project, one of the underlying technologies was a set of standards that built on the nascent web services model: WS-* and SOAP, the Simple Object Access Protocol. The intent was to build a framework that could deliver service-oriented architectures, where applications published defined service endpoints that could connect them both together and to clients and servers.
Microsoft intended to simplify what could be a complex process, writing WSDL (Web Service Definition Language) endpoint and message descriptions, building those endpoints, and constructing and parsing the XML messages used to connect services. Initially code-named Indigo, Microsoft’s web services tool was one of the key Longhorn technologies to survive the Vista reset, eventually shipping as WCF, the Windows Communication Foundation.
