How can I manage Users Roles without Using the inbuilt ASP.NET role management

 Hi,
I need to build a framework for loading links based on whether user has right to access a page.
I expect the application to load only those links that user can access when he logs in.
I actually want to load the links with web.sitemap. 
Can some advise me on how to do this without using the inbuilt ASP.NET role management
Thank you.

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