Windows Communication Foundation, known as WCF for short, is a wrapper around the .NET 2.0 framework, and is designed to facilitate the use of SOA for .NET applications in a simple and flexible way.

But why is WCF needed? The ASMX web services we used in the previous sections were the best way to implement a cross-platform SOA-based architecture. But when we need to implement ASMX services to interact with other platforms such as J2EE (Java Enterprise Edition, a platform for developing applications using the Java language), we will most probably need to use a mixture of technologies, such as ASMX web services along with Web Service Enhancements (WSE).

WSE is an implementation of the web services architecture for developers creating web services using ASP.NET and Microsoft .NET Framework client applications.WSE was introduced to help create scalable web services, with a special focus on security. Dealing with cross-platform security, as in, say, a .NET service...