In Chapter 21 you learned about Web services and how you can use them to provide simple communication between applications. You saw how you could use HTTP
POST techniques to exchange data with Web services, and how to use SOAP. Over the years since Web services were first made available to .NET developers, it has become apparent that although Web services are great, there is scope to extend this technology. Microsoft released the Web Service Enhancements (WSE) add-on to address this. WSE enabled Web service developers to include security for messages, routing techniques, and various other policies to improve Web services. Again, though, there was room for improvement.
Another .NET technology, remoting, makes it possible to create instances of objects in one process and use them from another process. Remoting makes this possible even if the object is on a different computer from the one that is using it. However, this technology, despite being a great improvement over previous technologies such as DCOM, still has its problems. Remoting is limited, and it isn't the easiest thing for a beginner programmer to learn.
Windows Communication Foundation (WCF) is essentially a replacement for both Web services and remoting technology. It takes concepts such as services and platform-independent SOAP messaging from Web services, and combines these with concepts such as host server applications and advanced binding capabilities from remoting. ...