When you build a WCF distributed system, you will typically do so by creating three interrelated assemblies:
The WCF Service assembly: This *.dll contains the classes and interfaces that represent the overall functionality you want to expose to external callers.
The WCF Service host: This software module is the entity that hosts your WCF service assembly.
The WCF client: This is the application that accesses the service's functionality through an intervening proxy.
As mentioned previously, the WCF service assembly is a .NET class library that contains a number of WCF contracts and their implementations. The key difference is that the interface contracts are adorned with various attributes that control ...