passing ASP.NET parameters to full screen Silverlight app

I've created an ASP.net web app (VS2010,C#), also I have a full screen silverlight page, this SL app should retrieve its username/password from my ASP.NET login page, what are my options? I have LOGIN.ASPX, then if user enters a special username/pass, my silverlight page (SL.ASPX) should open in the same window, how can I pass a number (representing my SL scene) from ASP.net to my SL app? I don't want my users to see this number (or text) in browser or addressbar. I h开发者_开发百科ave no silverlight control in my ASP.NET page as SL is in a whole new page what is the easiest way?

thanks

2 Crappy Solutions

1. You can either embed them in a hidden element of HTML and then from silverlight use js to navigate the dom of the page and find it.
2. You can make a web service call to a service that exists as part of your asp.net page and get them that way.