.Net 4.0 Is There a Business Layer "Technology"?

I have a theoretical question about the .net framework.

As I see it Microsoft gave us bunch of technologies for different layers.

We have the ADO.NET and with the more improved Ent开发者_C百科ity Framework for Data Access.

And ASP.NET for WEB UI. And even WCF for Facade and SOA.

But what in the middle, what do we have for the Business Layer? Is it just Referenced DLLs?

How do we deal with the Application Pooling this days? I remember using COM+ 10 yeas ago because the IIS couldn't handle the pressure.

Is Spring.Net is the best option available for injection?

Thanks, Ronny

For dependency injection, you can use the Unity Application Block from Microsoft Patterns & Practices.

You can also use the Managed Extensibility Framework.

EDIT: You might be looking for the entire patterns & practices group.