Question

Currently, we have many web applications (external & internal) developed using Classic ASP through .NET 2.0 technologies. Each of those web applications have their own login screen authenticating against their own custom database or using Windows authentication. Users have access to one or more of these applications, meaning they have to log out and log back into applications that they would like to access. All applications share some part of the back-end data sources. Also, the business logic is embedded in the UI in addition to being duplicated across applications because there is no code/business logic sharing. Screenshot #1 gives a brief idea of the existing architecture.

Screenshot #2 shows the suggested architecture, which I hope will help in faster development, code/business re-usability and may be simpler maintenance. Users will access either external or internal url. In external, users will provide credentials and will be authenticated against custom database. In internal site, users will be automatically logged in using Windows authentication. After creating some samples, I have begun to like ASP.NET MVC 3. It keeps business logic separate from UI and I also like the unit testing capabilities.

Here are my questions:

1. Based on what I have found on the web so far, multiple authentications are not feasible within a single website. My understanding is that I have to host one website for each type of authentication (Forms and Windows). How do I redirect users to common landing page after they are authenticated so they can see the modules (links/menus) that they are authorized to access? Should I have to publish the same code set (dlls and content) to both the websites?

2. Has anyone faced a similar architecture problem? If yes, could you please share the challenges that you faced and how you tackled them? What are the industry standards in designing applications of this sort?

3. Does the suggested architecture make any sense or is it a really bad design? Are there any drawbacks in doing this in ASP.NET MVC 3?

I would really appreciate your inputs.

Thanks in advance.

Answer 1

I would set up a seperate web site which only handles the windows authentication. I would then rely on something like OpenID and/or OAuth to ask for credentials/token to make sure to user has proper access.

The user that want to sign in using windows credentials go through that process because you are right in that a IIS server running windows authentication is hard to mix with other stuff.

You can set up some kind of claim based network of thrust in which you applications get thier credentials from trusted sources and through that process you can negotiate and control access privileges cross many web sites. As long as your not doing custom hosting or white label branding you can have everything in one place (or even if you did you could design it so that you have a central solution of handing out authentication tokens).