Passing SWT token from Azure ACS to my application
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I have created an ASP.NET MVC 4 WebApi application, which uses claims based authentication, and uses Azure ACS as a federated authentication. Everything works fine out of the box, by that I mean that I have configured my Azure ACS as an STS reference, I have added class for SWTSecurityTokenHandler to be able to read SWT tokens from ACS, and now when I go into a secure address in my browser, I get redirected to ACS page where I can select my Identity provider, after selecting one I log in to this IdProv, and then I get redirected to my application, which can read claims from the generated token.

Now my problem is, that I am trying to reimplement the same request->redirect->response path (from some identity provider to ACS and to my application) using just fiddler to imitate the requests and responses. I was able to get a token from my IdProv, pass it to ACS, and get an SWT token from ACS. 

But in whatever way I try to pass the ACS token to my application, it always redirects me to ACS IdProv selection page. I have no idea how to pass the token, so my application would try to use it. Can you guys instruct me on that?

I am asking about it, because I will want to create a JS client, which will invoke this login logic later on, that's why I won't be able to use ACS IdProv selection screen.

Am I doing something wrong, or my whole logic (to pass the token) is wrong? I would really appreciate some assistance, I have been struggling with that for almost a week now. 