Windows Communication Foundation

The Windows Communication Foundation (WCF), previously known as Indigo, is a free and open-source runtime and a set of APIs in the .NET Framework for building connected, service-oriented applications.

It is designed using service-oriented architecture principles to support distributed computing where services have remote consumers.

WCF implements many advanced Web services (WS) standards such as WS-Addressing, WS-ReliableMessaging and WS-Security.

Behaviors allow the developer to create custom processing, transformation, or inspection that is applied to messages as they are sent or received.

In addition to SOAP, WCF 4 supports non-SOAP XML, RSS, JSON, and binary formats for external communication via HTTP or HTTPS.

dot net three point windows stack diagram
This subsystem is a part of .NET Framework 3.0