I also heard a lot about the Windows Server App Fabric . The following is a summary of App Fabric white paper .
AppFabric Hosting Services (originally code-named "Dublin") doesn't create some entirely new hosting infrastructure. Instead, it builds on what's already provided by Internet Information Services (IIS) and Windows Process Activation Service (WAS). On this foundation, AppFabric Hosting Services adds extra capabilities for running and managing WCF services, including workflow services. Figure 7 illustrates this idea.
Windows Application Home
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