Role based authorization and Page access using Session in ASP.Net

If you're not utilizing Form Based Authentication, then the simple way is to create a Session Cooky at Page_Load event of each aspx page.

Pages reserved for admin create the Session("user") = "admin". Customer pages create the Session("user") = "customer".

Now, on user log-in, compare his "status" with that session cooky, then Load (or don't) the page accordingly.