If you are within an enterprise and want to implement an OAuth/OpenID provider for your company infrastructure and you don’t want to pay top premium dollars for a commercial architecture, there is a solution. Thinktecture Identity Server provides a nice implementation that respect a lot of standards and protocols. You will want to take a look at that.

As for the rest, ASP.NET and Async Web Pages as well as some AngularJS code.

Enjoy!

Thinktecture Identity Server (OAuth + OpenID)

thinktecture/Thinktecture.IdentityServer.v2 · GitHub (github.com)

Thinktecture Identity Server - Configuration, Customization - CodeProject (www.codeproject.com)

ASP.NET & MVC

Writing Asynchronous Web Pages with ASP.NET- Part 1 | Brij’s arena of .NET on WordPress.com (brijbhushan.net)

AngularJS

Cascading DropDownList with AngularJS and ASP.NET MVC | TechBrij (techbrij.com)

Displaying ModelState Errors with AngularJS in ASP.NET MVC | TechBrij (techbrij.com)