An Open Source Project, Can Teach Membership and Role Management For .NET

I want to see a basic project to learn how to organize membership and role management. Can you give me some open source project link about it?

From stackoverflow

• If you are interested in an asp.net user membership example, N2 has a feature named User registration & Login parts.

  N2 is an open source lightweight CMS framework. One benefit of it's modular and lightweight approach is that the CMS can be integrated into existing ASP.NET solutions and ASP.NET MVC.